User talk:Sandbh

Regarding solving the issue between ourselves
User:Sandbh, I have been trying to de-escalate the issue at WT:ELEM. I ask that you read that first before you continue at the ArbCom case, that both of us did not want.

A summary:
 * 1) I am no longer seeking to RFC the group 3 issue right now. You have given information that something from Scerri is coming, I think it makes sense to wait for that. By the time that comes out, we will know something about the IUPAC project's deliberation and things will almost certainly be less controversial, even though probably we will wait till the actual report if not later (its acceptance) to do something if it makes sense.
 * 2) I am no longer seeking to remove categories. User:Jehochman has given some statements there that have made me consider that categories can after all be consistent with policy, so I no longer have an objection to them.
 * 3) Proposed compromise that is basically: split the nonmetals 3-way as you prefer, with "other nonmetals" as temporary placeholder category to stop any arguing while we are in the spotlight and work together.

I think the first two points mean that almost the whole issue has vanished. I am not seeking a change from what you prefer on the two main issues! I do this because I feel that keeping things civil in the project through compromise is more important than my own personal preferences and that working on the rest of the article is more important than these issues. And also because of what EdChem has told us about ArbCom and it not being a good option for our project at this time. Keeping us together is more important to me than "winning" some dispute or another. So far R8R, DePiep, and YBG have responded favourably; if you are OK with this first, the thing is resolved. I hope you will be OK with it because it is in both cases basically your preference! I do not want to see any of the bad outcomes EdChem has mentioned on his talk page, as may be an outcome if it proceeds to ArbCom, and that is why I am prioritising ending the dispute over everything else first even if it is not ending it in a way that I would have preferred initially. That's not as important.

And on the nonmetals breaking up you propose, you have my support for the break. I simply propose "other nonmetals" for now as a temporary thing that everyone agrees is at least technically correct and can probably live with to solve the issue while it is in the spotlight. That is just because I think you will have more luck doing a change to such a boring but accurate name first before seeking to change that to something more descriptive later. Or if you prefer we can simply agree to stick to the status quo first since the two big issues we clashed on are solved. Your choice, I will go with it over ArbCom proceedings. Double sharp (talk) 00:10, 14 November 2020 (UTC)


 * It's all good. More to follow. Sandbh (talk) 00:32, 14 November 2020 (UTC)
 * Thank you. User:EdChem suggested that we provide a joint statement on his talk page: do you think it'd be good for the two of us to issue a joint statement saying that the two of us have decide jointly to end all disputes between ourselves in this way? Double sharp (talk) 00:34, 14 November 2020 (UTC)
 * Yes, that's the go. Sandbh (talk) 00:35, 14 November 2020 (UTC)
 * Excellent, would you prefer to draft it yourself or have me try? I was thinking of something along the lines of replacing our current posts as "The two of us have discussed between ourselves at User talk:Sandbh and WT:ELEM and agreed to end the dispute by accepting the current status quo for (1) the group 3 issue until further information is received from the relevant IUPAC project, and (2) the existence of a category colouring. On the issue of (3) splitting the nonmetals, Double sharp has agreed to support Sandbh's proposal for splitting, and to postpone discussion on the name of the new category until later. We have decided to end all hostilities and draw a line behind past accusations of the other not following policy in other ways and cooperate instead." You can edit it the way you prefer, it is a statement of cessation of hostilities and reconciliation after all. ^_^ Double sharp (talk) 00:39, 14 November 2020 (UTC)


 * Yes, give it a try. I'd prefer to remove all references to content and keep it as simple as possible. How do you see that? I'll look closer at the words now. Sandbh (talk) 00:42, 14 November 2020 (UTC)
 * Anything you prefer on it is OK. ^_^ How about "The two of us have discussed between ourselves at User talk:Sandbh and WT:ELEM and agreed to end the dispute, to withdraw all hard feelings about each other from all previous cases, and to return to our pre-2020 collaborative relationship as WP editors." Is that simpler for you? Double sharp (talk) 00:45, 14 November 2020 (UTC)


 * I was going to say:


 * Joint statement by Double sharp and Sandbh. The two of us have discussed the ARBCOM filing at User talk:Sandbh and WT:ELEM. We've agreed to withdraw, and move past, previous allegations, and to continue to work together. We recognise we agree on some things, and disagree in other areas on philosophical grounds. We intend to not bludgeon one another (so to speak) on philosophical grounds but to engage in civil discourse. We've mostly done that anyway for the past nine years, and recognise that our philosophical differences should not escalate to the point of detracting from the WP:ELEM experience; requiring ANI involvement; or a referral to ARBCOM.


 * Could you incorporate some of that into your proposed form of words? — Preceding unsigned comment added by Sandbh (talk • contribs)
 * I'm fine with taking it as-is, actually. But if I may suggest one thing: could we add four words "engage in civil discourse as becoming of Wikipedians "? Double sharp (talk) 01:04, 14 November 2020 (UTC)
 * Just a thought. I wonder if a joint apology to the community for wasting time at ANI would be appropriate? YBG (talk) 01:08, 14 November 2020 (UTC)
 * Certainly. Perhaps add a sentence saying "We further apologise to the community for wasting their time with multiple ANI threads and pledge not to do any such thing again"? Double sharp (talk) 01:09, 14 November 2020 (UTC)

Here it is then:


 * Joint statement by Double sharp and Sandbh


 * The two of us have discussed the ArbCom filing, at User talk:Sandbh and WT:ELEM, with input from User:YBG, and cognisant of observations by User:EdChem.


 * We've agreed to withdraw, and move past, previous allegations, and to continue to work together.


 * We recognise we agree on some things, and disagree in other areas on philosophical grounds. We intend to not bludgeon one another (so to speak) on philosophical grounds but to engage in civil discourse, as becoming of Wikipedians. We've mostly done that anyway for the past nine years, and recognise that our philosophical differences should not escalate to the point of detracting from the WP:ELEM experience, requiring ANI involvement, or a referral to Arbcom.


 * We apologise since maybe after the first few rounds we should've figured that out rather than sending each other to ANI.


 * We thank X for bringing the matter to ArbCom.

Is that OK? — Preceding unsigned comment added by Sandbh (talk • contribs)
 * Looks mostly fine to me. Should we perhaps mention that we have decided to resolve the dispute by a compromise that both parties find acceptable, or is it too soon to say that yet before you've confirmed what you'd find to be one? ? And do you or YBG think we should mention that neither of us wanted to file the ArbCom in the first place? (I think you said it on my talk page; I'm not sure if I said it or if I was considering the situation offline first, but definitely when I got the talkpage message from CaptainEek I had no intention to do so and was surprised to find it started.) Double sharp (talk) 01:36, 14 November 2020 (UTC)
 * Need to sleep now, will look at the situation tomorrow. Double sharp (talk) 01:39, 14 November 2020 (UTC)
 * I'm fine with or without the apology. I only wanted you two to consider including it. If you considered it and chose not to include it, I would be fine with that too. I only caution you to make sure that you don't say something that might be interpreted as a promise to never ever initiate anything at ANI. I don't think your statement means that, but I'm not sure what someone else might think.
 * Here's a thought: "We recognize that X was justified in brining this to ArbCom because we had wasted so much commuity time by our multiple ANI threads, for which we apologize." And, if the ArbCom filing helped you to rethink things, it might be nice to say so and to thank X. YBG (talk) 01:52, 14 November 2020 (UTC)
 * Hey, that's not a bad idea. Double sharp (talk) 11:26, 14 November 2020 (UTC)

I've changed the last line (in our JS, above) to a simple thank you. Upon reflection, I doubt we have anything to apologise for. Each of us thought we were pursuing the matter in line with the way we understood "how things work around here" i.e. via ANI. Upon reflection, it seems to me that the real issue is, as I've alluded to, is a lack of guidance for aggrieved parties as to the unwritten rules re how things work, or don't work, at WP:ANI. I've also said I don't believe ANI is well set up to handle matters such as these, which span conduct-content-policy. Now, it may be that the community view is that ANI should not deal with such matters. If so, that's fine but there does not appear to be any guidance to that effect. Anyway these are things that can be worked on later. In the meantime, how does the draft of our joint statement look now? Sandbh (talk) 23:14, 14 November 2020 (UTC)
 * Did you get my ping? Sandbh (talk) 05:12, 15 November 2020 (UTC)
 * Apparently I didn't see it with all the pings flying around, but I agree with what you currently have written and said. Though I wonder if it might be better to apologise in good faith anyway, since maybe after the first few rounds we should've figured that out and not kept sending each other there. Double sharp (talk) 11:46, 15 November 2020 (UTC)

Righto. Looks OK now? Sandbh (talk) 22:43, 15 November 2020 (UTC)
 * Yup. Incidentally X = CaptainEek, for when we post it. ^_^ Double sharp (talk) 22:46, 15 November 2020 (UTC)
 * I'll now post the JS to my comments section. Sandbh (talk) 22:52, 15 November 2020 (UTC)
 * Great! Double sharp (talk) 22:56, 15 November 2020 (UTC)

Trifurcating the nonmetals
I have raised the subject at Wikipedia_talk:WikiProject_Elements (similar to what is proposed at your RFC), since we both seem to be in favour of some kind of 3-way division of nonmetals into H-C-N-O-P-S-Se, F-Cl-Br-I "halogen nonmetals", and He-Ne-Ar-Kr-Xe-Rn "noble gases". Reading the responses, I seem to understand two things:


 * 1) In general, there is some feeling that we should not spend too much time on this, and should just decide on something quickly and get to working on the article. That seems to suggest that we should be able to just implement the result, as we did for the 2013 polyatomic/diatomic split, or for the 2012 recolouring of polonium, of any short discussion. I.e., similar to whatever we do when we discuss changing the article. Rather than prolonging the issue with an RFC. I understand your feeling that our project should not decide for the whole of WP, but (1) we did that before, and (2) that is essentially what happens for pretty much every article: usually, it is a small bunch or even just one editor writing something in the first place. Haven't we already spent enough of the community's time with this?
 * 2) has no objections to either changing or not changing. Looks like  would prefer not to (because of "halogen nonmetals" mostly), but he also says We could do it, and it wouldn't be the end of the world, and doesn't mind "other nonmetals".

So, in order to make you not have to read the whole thing if you don't want to: what do you think of doing the 3-way split I understand you favour immediately (H-C-N-O-P-S-Se + F-Cl-Br-I "halogen nonmetals")? The temporary concession would be that the first category gets called "other nonmetals", with absolutely no prejudice to a future RFC or any other process to change later from "other nonmetals" to some more distinctive name.

I just suggest it because I get the feeling that if we try to push further now, we'll not get support, we'll rather get people tired of talking about things, we'll get people annoyed that the process is taking too much time, what little support we do get gets divided out of existence by too many possibilities, and we won't get even half of what we wanted. But if we stop at "other nonmetals" temporarily and just think of it as another thing to WP:BRD about just like new periodic table pictures, then we may get something relatively painlessly, and you may be able to push it the rest of the way later. So I suggest this to you out of pragmatism and a desire to resolve the conflict very quickly with some of what the whole thing was meant to achieve done, rather than force it to run for another month and possibly with nothing to show for all the words that were exchanged. I don't want a good idea to get stuck this way, to borrow your words. Just to consider, there's no obligation to say yes or no or anything. Double sharp (talk) 17:26, 15 November 2020 (UTC)


 * Thanks. I don't mind what the will of the community would be wrt the RFC. I feel it would be worthwhile testing it. Sandbh (talk) 04:27, 17 November 2020 (UTC)

Recent post at WT:ELEM
Sandbh, I have come here after reading this post of yours at WT:ELEM that was addressed to, and in which you pinged and. The edit summary that you used was "Faced with a choice of affirming R8R or DePeip", which I took as concerning sign of a battleground mentality, an impression that the post confirms, IMO.

Firstly, I ask that you revert that post as it is not appropriate for that project talk page, either in tone or in content.

Secondly, if you want to discuss editing behaviour with DePiep, starting a post at his user talk page would be a much more appropriate venue. Given the recent conflicts, some clearing of the air is understandable / desirable and potentially very productive. However, your tone comes across to me as inconsistent with your request at the end for reflection. You describe DePiep as combative in terms that are themselves combative, and begin your post with the assertion that "[f]aced with a choice of affirming R8R or DePeip, I affirm R8R." WP editors are meant to all be on the same side, working towards quality encyclopaedic content. Taking sides should follow from policy and belief in the best interests of the project and our readers, and not be based on who made what proposal.

Thirdly, this is one reason that your post is inappropriate for a project talk page. Faced with two proposals, you express your position based on personalities. Your post does not address the policy merits of either proposal, nor does it add anything to determining a consensus of editors on the content question.

If you want to raise your concerns with DePiep, that's fine, you have that right. I would advise that you reconsider your approach and seek a way to address your concerns in the interests of future collaboration and the project. If you want to contribute to the content discussion at WT:ELEM, that's also fine – but please express a view that is content and policy focussed. Ideally, try to contribute without mentioning any other editor and only looking at the positions being described. EdChem (talk) 02:27, 16 November 2020 (UTC)

PS: I  note that  posted to  earlier in that thread, "looking for your acknowledgement that [some of DePiep's behaviour] was not appropriate and for a commitment that [DePiep] would not do any of this again." DePiep's reply, while likely not exactly what R8R wanted, did include that
 * "The statement by Double sharp includes the topic of "problematic behaviours": "end ... and not to restart". I am very well aware that this is part of the proposal, and that the "self reflection" is included. However, it is not required or proposed to do so publicly — on the contrary: it says not to "squabble about who was 'right'". I read this to mean: be open to (self-)criticism into improvement, and that is what I can sign up to. ...
 * Your question raises the possibility that this thread too becomes a sort of ANI complaint-solving (or, more likely, -not-solving). That would take out all effectivity of the proposal, because that route is what has failed. ...
 * Please keep in mind that WP:ELEMENTS has left the ani-level of dispute resolution; as EdChem described the Project now is in more serious danger wrt (our) future editing options. This proposal requires a change of attitude of us all, and will take lots of energy, aimed upward, to make it work."

stated (as the OP) that he is "happy enough with this statement by DePiep. If asking for public statements runs the risk of jeopardising this quick resolution, then I feel we should not insist on it." I have said several times that some degree of clearing the air is beneficial, but I have to agree with DePiep that placing blame or re-hashing an ANI thread would be destructive and should be avoided. Self-reflection and change are needed, but this does not need to be done publicly. Being able to read constructive criticism, reflect on it, and then quietly change directions is enough, and a massive improvement from instinctive self-defence or rejection of comments based on who made them.

Consequently, if you do choose to remove your ELEM post (which I hope), and if you do choose to approach DePiep directly, recognise that your desire for a formal acknowledgement of problems etc may come in the form of a restatement of the above – that DePiep recognises the requirement that all change and put in energy to make editing work in the future. If that is his choice and he does not want to self-reflect in public, I think we should accept that and let his actions going forward speak to the meaning he puts into those words.

On a personal note, I am hoping to see changes from everyone named in the case request and the broader ELEM community. If that happens, we can perhaps welcome greater participation from others as well. EdChem (talk) 02:47, 16 November 2020 (UTC)

Thank you, I'm considering your thoughts. Courtesy ping:.

There is some missing context I ask you to please consider.

I posted at WP:ELEM since the thread was about deciding between ourselves.

It was started by DS, at WP:ELEM, with contributions by DePiep, and R8R. DePiep closed with the comment, "Waiting for Sandbh to reply here."

I did so, acting upon DePiep's request.

On affirming DS, I originally wrote, "supporting". I changed it to "affirming" to show that I was not supporting one party or the other. Rather I wanted to show that I basically agreed with Double sharp. My intention was then to let the rest of my post do the talking.

EdChem, you often write that matters of conduct should not be discussed at WP:ELEM. I agree in principle. After nine years of interacting with DePiep (sometimes good; more often undesirable or unpleasant) at WP:ELEM and noticing the impact of these interactions on other WP:ELEM members, the time had come, I felt, to discuss the matter on the project talk page, since these interactions impact the entire project, noting DePiep's invitation.

The straw that broke the camel's back was the post by DePiep, at the WP: ELEM talk page re me "still editing wide and rough". I was also influenced by Robert McLenon's comment at ARBCOM, re "Is User:DePiep a net negative to the encyclopedia?" not to mention the comments by four other non-WP:ELEM editors, at ArbCom.

As Softlavender noted at WP:ANI, "I think at this point, DePiep is going to end up at ArbCom and/or or long-term blocked if he continues in the behavior patterns he has demonstrated all over Wikipedia". Depiep's conduct does not represent a one off incident, or a series of incidents; he had demonstrated this behaviour all over WP, and continues to do so as per my examples, with diffs.

In this context could you reconsider my post to WP:ELEM? I am also curious to know what prompts you to take such an interest in my conduct, whereas, regardless of what DePiep does, you do not balance your comments with a corresponding appraisal of his actions. Do you know he is under an open-ended warning of an indefinite ban from WP, the instant he demonstrates a further occurrence of misconduct? How do you think he managed to acquire that?

I await my colleague R8R's thoughts in this matter. I do not mind where the discussion take place as long as I'm pinged in.

I agree with Double sharp's request for a quick resolution, which Double Sharp and I, by mutual agreement, have achieved.

Recall there were two parts to the ANI matters: (1) concerns re DePiep; and (2) concerns re myself and Double sharp. The latter item has been resolved.

Recall too, that neither Double sharp nor I summoned DePiep to ArbCom.

Thank you EdChem. I intend to review my position in this matter tomorrow. Sandbh (talk) 04:34, 16 November 2020 (UTC)


 * I will leave my comments at WP:ELEM. They can be regarded as a partial calling to account of DePiep's conduct, before his WP:ELEM peers. After nine years of experiencing the alleged conduct at WP:ELEM, I do not regard this as unreasonable. We are all on the same side, even DePiep. I am not seeking to assign blame. That said, I no longer wish to walk over broken glass in my interactions with DePiep.


 * I'm not inclined to start the conversation at DePiep's talk page. I've seen what happens. DePiep bans the poster from his talk page, and the conservation is binned.


 * The four non-WP:ELEM editors at ArbCom have raised valid concerns about DePiep.


 * I expect that is all I have to say in this matter re DePiep, which is primarily about conduct, not content, recalling that neither R8R nor I summoned DePiep to ArbCom. Sandbh (talk) 00:48, 17 November 2020 (UTC)
 * Sandbh, I know that I don't have the history of having participated in ELEM for years. I have watched / commented on ArbCom for years, however.  Whatever your intention, the effect of your actions is to make a case much more likely.  It is my opinion that that case will not end well for you.  Within the context of a pending case and with statements about moving forwards, your actions appear to be BATTLEGROUND behaviour.  ArbCom pays close attention to actions taken once a case request is lodged and through to its conclusion.  Consequently, I advise you that your present approach can be expected to increase the chances of you being seen as disruptive and support the conclusion that your removal from the topic area is in the best interests of the encyclopaedia and its readers.  Whether you think this is fair or reasonable, I am describing what I believe is the situation.
 * FYI, I have encountered before and am aware that he is not always the easiest editor to work with.  You asked why I have not be speaking with him about his actions.  The reason is simple.  I have not seen actions / comments in the ELEM area since my involvement that I have believe necessitated my posting to him as I am presently posting to you.  Had he posted at ELEM along the lines that you did, I would certainly have spoken to him.  When I saw his concerns at 's page, I was concerned at what might develop.  However, once I recognised that DePiep had good reason to be aggrieved, I thought it far more important to address the actual issue than to look to how it was raised.  I don't want to see an ArbCom case, but avoiding it means that a plausible and functional way forward is available.  That means all the named parties, which now also includes, need to find a way to work together.
 * As I noted above, DePiep's response might not have been what R8R or you wanted, but it did state that a change of attitude is required, that self-reflection will be involved, and that a willingness to be open to criticism (from oneself and others) and to make improvements is required. DePiep is correct that the process for achieving such changes need not be public.  You and R8R may want a public apology, etc, but seeking one is not helping to end this dispute.  DePiep's actions as time goes by will show whether change has occurred.  If it has, then no more is necessary... if it has not, then steps can be taken based on subsequent actions.  DePiep has made an encouraging statement and is asking for his future actions to be the proof of his intentions.  You can make an equal gesture by accepting his word and allowing him the time and space to show his intent.
 * I note that no one has posted a great list of posts / comments / actions for which they would like to see you apologise. If anyone were to post one, I would ask them to remove it as counter-productive... but I suspect that you would feel aggrieved (just as DePiep does), that you would rather not post a long self-reflection on your mistakes and mis-judgements, etc.
 * Please, stop and reflect on what you want to achieve. If it is a return to productive editing, please act to help that to happen.  If it is a contentious and likely very unpleasant few weeks with ArbCom, likely resulting in multiple topic bans (including your own), well... you are already acting to make that happen.  EdChem (talk) 04:24, 18 November 2020 (UTC)

Thank you I welcome your advice. I'm not so concerned about a case but note your own concerns. At this time, I'm happy to be held accountable for alleged BATTLEGROUND behaviour, as you put it, noting I haven't read this policy yet. Recall there are two parts to the ARBCOM filing, which neither DS nor I filed. The first concerns content-policy-conduct ANI matters pertaining to myself and Double sharp. As per our joint statement, DS and I have resolved our differences and are moving on.

The second part concerns ANI conduct by DePiep.

He was not a part of the ARBCOM original filing and was added later by the report filer. Subsequently, four other non-WP ELEM editors raised concerns about DePiep's conduct. As I noted, Softlavender presaged DePiep was heading to ARBCOM.

DePiep effectively asked to be a party, in some fashion, to the joint agreement that DS and I had reached.

R8R asked DePiep for an acknowledgement that DePiep's conduct was not appropriate and for a commitment that he would not do any of this again.

I have acknowledged my inappropriate conduct at WP:ANI, posted an apology at WP:AN, and have lost track of all the other apologies I posted at WP:ANI to anybody who had felt upset by my conduct. I gave commitments at ANI to Double sharp to not engage in the kinds of behaviour that had previously upset DS (with some caveats).

DePiep declined R8R's request. DePiep said he was waiting for my response.

I posted my response, including diffs, honestly explaining my reasons for affirming R8R, based on my experience in dealing with R8R at WP:ELEM over the past nine years. We do not always agree but R8R is a thorough gentleman, in my experience.

I could have said nothing to DePiep apart from affirming R8R. I instead spoke honestly, listing my considerations. I intended this to be for the benefit of DePiep, as part of his self-reflection.

I've now read WP:BATTLEGROUND, and its advice that, "If a conflict continues to bother you, take advantage of Wikipedia's dispute resolution process." ARBCOM is the ultimate DR process.

I once again note that neither DS nor I filed the ARBCOM report. As far as I was concerned, the only matter of concern was the differences DS and I had. These have been resolved. DePeip was a late addition added by another non-WP:ELEM editor, followed by four other non-WP:ELEM editors raising concerns about DePiep. If there is that much interest in DePiep's conduct, from editors outside of WP:ELEM, so be it.

I'll talk to about this. Sandbh (talk) 05:24, 18 November 2020 (UTC)
 * If a case starts, ArbCom will look at the ANIs, they will look at the evidence that anyone chooses to present, and that you and Ds have agreed to de-escalate your conflict will not stop them acting against you if they view your recent editing (before and since the case request) as a cause of disruption that they conclude needs to be stopped. That neither you nor Ds launched the case will not matter.  Your ongoing conflict with DePiep will matter, as will continuing to disregard what DePiep has said about change.  These will remain true no matter what you think should happen / be done by ArbCom.  Whether you believe me or not, and perhaps ask others if you doubt me, at present a case is very likely to see you get a topic ban at minimum.  EdChem (talk) 05:44, 18 November 2020 (UTC)

Thank you. Re, "as a cause of disruption that they conclude needs to be stopped" DS and I have agreed a way forward, and there is now no such disruption needing to be stopped. Does this not matter? Sandbh (talk) 05:50, 18 November 2020 (UTC)
 * Sure, it matters... but it is not the only matter. They will look at actions post that agreement, I'm sure, and it could be strengthened by what they see.  However, disruption is a broad term.  Your post to DePiep can be a form of disruption.  Disruption can be wall-of-text posting in threads, or editing inconsistent with policy, or actions against agreed consensus, or unwillingness to drop the stick / move on from conflicts,  or ...  – it all depends on what is presented in evidence, but the ANIs certainly create the impression of ongoing project dysfunction and disruption from some participants.  EdChem (talk) 06:01, 18 November 2020 (UTC)

. I think I'm OK with that. The ANI's involving DePiep were closed without action. The 1st one was closed b4 I could provide the diffs; the second was closed without, IMO, a proper examination. Even you've commented about a less than impressive ANI close decision. I note DePiep's addition to the filing attracted interest from the other four editors. As for my post responding to DePiep, transparency is important for me. Sandbh (talk) 06:11, 18 November 2020 (UTC)

Regarding a possible future RFC
If my second proposed compromise doesn't work, then I'll agree with you to proceed to an RFC. So I'd like to ask in preparation for that eventuality: would you be OK with me offering my own PT colouring proposal as an additional option?

I would like for clarity something along the lines of a bunch of coloured-in PT's with proposal numbers so that everyone is 100% clear what they're voting for. But looking at the sources (Britannica, LANL, RSC, and ACS) makes me want to revisit group 12 in an RFC, and that's far away from your proposed region.

So I think the clearest way to go for coordination would be something along the lines of:

Question: Please choose among the following proposals for categorisation in the main Periodic table on Wikipedia, for general use as a default when the context does not clearly demand a more relevant different categorisation.


 * Proposal 0 [status quo]: [illustration]
 * Proposal 1: [illustration]
 * Proposal 2: [illustration]
 * hopefully not too many to not bore everyone to death

We should presumably spend some time drafting it so that all the illustrations are in the same format. That way, we know people are commenting on the precise categories, not about any other differences.

Are you OK with this proposed procedure, or would you rather do it another way? Double sharp (talk) 23:27, 16 November 2020 (UTC)


 * P.S. I would also like to seek 's comments on whether this is an appropriate RFC question. Double sharp (talk) 23:27, 16 November 2020 (UTC)
 * I'd like to make any proposal to revisit group 12 the subject of a separate RFC. Thank you. Sandbh (talk) 04:18, 17 November 2020 (UTC)
 * Not a problem with me at all, as long as we get to discuss it in some appropriate way. ^_^ Double sharp (talk) 09:38, 17 November 2020 (UTC)
 * I've added it to the RFC roster at WT:ELEM; please let me know if that is OK with you or not. Double sharp (talk) 10:02, 17 November 2020 (UTC)
 * Great! Sandbh (talk) 10:38, 17 November 2020 (UTC)
 * Excellent. I'll start drafting it, then. ^_^ Double sharp (talk) 10:58, 17 November 2020 (UTC)

P.S. I'd like to request a hold on having your nonmetal RFC go live until I hear comments from both of you about the astatine thing, if you don't mind. (Because if my At proposal doesn't gain immediate consensus to go live, then I would like to add it somehow to your nonmetal RFC as an extra option if you're agreeable.) Double sharp (talk) 22:06, 17 November 2020 (UTC)
 * I'll post my comments re At etc today, and look again at the nonmetal RFC. More later. Sandbh (talk) 22:43, 17 November 2020 (UTC)

RFC's: procedure
I've read your response today. Thank you, it is thought-provoking. Now I'm waiting on R8R's response, but I wanted to talk to you first about procedure.

It seems that as they evolve our proposals are diverging rather than converging. That's not so good for an intra-project consensus, but it definitely is a reasonable reflexion of a contest of ideas. I agree with you that an RFC will be the best way to go.

However, I worry that me offering my current view as an option on your RFC will needlessly confuse the issue as it is diverging too far away. Yours is basically taking a split into halogen nonmetals and something else as the default trifurcation view, whereas mine is not necessarily about that alone. My view for a colouring now would not only revisit group 12 (which we've agreed to put in a different RFC), but also astatine (as previously stated), and quite possibly (assuming I don't change my mind shortly) also polonium. (As for why, this is because LANL and ACS call polonium a metalloid. Scientifically seems to me that it is almost at antimony territory in some ways in terms of losing metallic character while still having it just barely win out, to be honest. You can partly thank User:Jehochman for this one since he suggested LANL, BTW.) It seems to me that it would be unfair to you to have all these issues conflated with your RFC which is about one thing only; yet each of our current views excludes the other. It also seems to me (although that is secondary) that it would also be unfair to my current proposal to do that, because that would force each of its three parts (group 12, polonium, astatine) to be discussed separately.

Therefore, I would like to ask: would you be OK with me starting my RFC as a simple support/oppose for the colouring below first, perhaps within a day or two (to give R8R some time to respond to At as a halogen)?

(Yes, it is exactly the pre-2012 colour scheme prior to all our ELEM discussions, with the exception of Cn for which uncolouring is justified by the theoretical study pointing out that the experimental results' interpretation may have been mistaken. Uncolouring Cn is probably the one thing on the talk page that is totally agreed at this point, TBH! ^_^)

My logic is that it doesn't make sense for mine to be conflated with yours – it is too different – but someone's has got to go first, and since mine is a general, one-option one it may be easier if it goes first. I do not ask for your support obviously for the option; I don't expect it in the first place. But I just want to see if you would be OK with me starting an RFC in a day or two at Talk:Periodic table to see how it goes. Double sharp (talk) 00:37, 18 November 2020 (UTC)


 * Will look at shortly. Sandbh (talk) 00:55, 18 November 2020 (UTC)

P.S. I've changed my proposal to the even earlier pre-2010 colour scheme to be absolutely neutral, because that is before any of us ever touched the template, whether you, me, or R8R. And also to match ACS/LANL better. Sorry if this causes confusion. (The one and only difference is that tennessine is now coloured in, because this scheme is so old that Ts had not even been discovered yet.)

{| class="navbox collapsible" ! colspan="32" | ! colspan="32" |
 * width="3.125%" style="background-color:#a0ffa0"|H
 * width="3.125%" colspan="30" |
 * width="3.125%" style="background-color:#c0ffff"|He
 * style="background-color:#ff9d9d"|Li
 * style="background-color:#ffdead"|Be
 * colspan="24" |
 * style="background-color:#cccc99"|B
 * style="background-color:#a0ffa0"|C
 * style="background-color:#a0ffa0"|N
 * style="background-color:#a0ffa0"|O
 * style="background-color:#ffff99"|F
 * style="background-color:#c0ffff"|Ne
 * style="background-color:#ff9d9d"|Na
 * style="background-color:#ffdead"|Mg
 * colspan="24" |
 * style="background-color:#cccccc"|Al
 * style="background-color:#cccc99"|Si
 * style="background-color:#a0ffa0"|P
 * style="background-color:#a0ffa0"|S
 * style="background-color:#ffff99"|Cl
 * style="background-color:#c0ffff"|Ar
 * style="background-color:#ff9d9d"|K
 * style="background-color:#ffdead"|Ca
 * style="background-color:#ffc0c0"|Sc
 * colspan="14" |
 * style="background-color:#ffc0c0"|Ti
 * style="background-color:#ffc0c0"|V
 * style="background-color:#ffc0c0"|Cr
 * style="background-color:#ffc0c0"|Mn
 * style="background-color:#ffc0c0"|Fe
 * style="background-color:#ffc0c0"|Co
 * style="background-color:#ffc0c0"|Ni
 * style="background-color:#ffc0c0"|Cu
 * style="background-color:#ffc0c0"|Zn
 * style="background-color:#cccccc"|Ga
 * style="background-color:#cccc99"|Ge
 * style="background-color:#cccc99"|As
 * style="background-color:#a0ffa0"|Se
 * style="background-color:#ffff99"|Br
 * style="background-color:#c0ffff"|Kr
 * style="background-color:#ff9d9d"|Rb
 * style="background-color:#ffdead"|Sr
 * style="background-color:#ffc0c0"|Y
 * colspan="14" |
 * style="background-color:#ffc0c0"|Zr
 * style="background-color:#ffc0c0"|Nb
 * style="background-color:#ffc0c0"|Mo
 * style="background-color:#ffc0c0"|Tc
 * style="background-color:#ffc0c0"|Ru
 * style="background-color:#ffc0c0"|Rh
 * style="background-color:#ffc0c0"|Pd
 * style="background-color:#ffc0c0"|Ag
 * style="background-color:#ffc0c0"|Cd
 * style="background-color:#cccccc"|In
 * style="background-color:#cccccc"|Sn
 * style="background-color:#cccc99"|Sb
 * style="background-color:#cccc99"|Te
 * style="background-color:#ffff99"|I
 * style="background-color:#c0ffff"|Xe
 * width="3.125%" style="background-color:#ff9d9d"|Cs
 * width="3.125%" style="background-color:#ffdead"|Ba
 * width="3.125%" style="background-color:#ffbfff"|La
 * width="3.125%" style="background-color:#ffbfff"|Ce
 * width="3.125%" style="background-color:#ffbfff"|Pr
 * width="3.125%" style="background-color:#ffbfff"|Nd
 * width="3.125%" style="background-color:#ffbfff"|Pm
 * width="3.125%" style="background-color:#ffbfff"|Sm
 * width="3.125%" style="background-color:#ffbfff"|Eu
 * width="3.125%" style="background-color:#ffbfff"|Gd
 * width="3.125%" style="background-color:#ffbfff"|Tb
 * width="3.125%" style="background-color:#ffbfff"|Dy
 * width="3.125%" style="background-color:#ffbfff"|Ho
 * width="3.125%" style="background-color:#ffbfff"|Er
 * width="3.125%" style="background-color:#ffbfff"|Tm
 * width="3.125%" style="background-color:#ffbfff"|Yb
 * width="3.125%" style="background-color:#ffbfff"|Lu
 * width="3.125%" style="background-color:#ffc0c0"|Hf
 * width="3.125%" style="background-color:#ffc0c0"|Ta
 * width="3.125%" style="background-color:#ffc0c0"|W
 * width="3.125%" style="background-color:#ffc0c0"|Re
 * width="3.125%" style="background-color:#ffc0c0"|Os
 * width="3.125%" style="background-color:#ffc0c0"|Ir
 * width="3.125%" style="background-color:#ffc0c0"|Pt
 * width="3.125%" style="background-color:#ffc0c0"|Au
 * width="3.125%" style="background-color:#ffc0c0"|Hg
 * width="3.125%" style="background-color:#cccccc"|Tl
 * width="3.125%" style="background-color:#cccccc"|Pb
 * width="3.125%" style="background-color:#cccccc"|Bi
 * width="3.125%" style="background-color:#cccc99"|Po
 * width="3.125%" style="background-color:#ffff99"|At
 * width="3.125%" style="background-color:#c0ffff"|Rn
 * style="background-color:#ff9d9d"|Fr
 * style="background-color:#ffdead"|Ra
 * style="background-color:#ff99cc"|Ac
 * style="background-color:#ff99cc"|Th
 * style="background-color:#ff99cc"|Pa
 * style="background-color:#ff99cc"|U
 * style="background-color:#ff99cc"|Np
 * style="background-color:#ff99cc"|Pu
 * style="background-color:#ff99cc"|Am
 * style="background-color:#ff99cc"|Cm
 * style="background-color:#ff99cc"|Bk
 * style="background-color:#ff99cc"|Cf
 * style="background-color:#ff99cc"|Es
 * style="background-color:#ff99cc"|Fm
 * style="background-color:#ff99cc"|Md
 * style="background-color:#ff99cc"|No
 * style="background-color:#ff99cc"|Lr
 * style="background-color:#ffc0c0"|Rf
 * style="background-color:#ffc0c0"|Db
 * style="background-color:#ffc0c0"|Sg
 * style="background-color:#ffc0c0"|Bh
 * style="background-color:#ffc0c0"|Hs
 * style="background-color:#ffc0c0"|Mt
 * style="background-color:#ffc0c0"|Ds
 * style="background-color:#ffc0c0"|Rg
 * style="background-color:#ffc0c0"|Cn
 * style="background-color:#cccccc"|Nh
 * style="background-color:#cccccc"|Fl
 * style="background-color:#cccccc"|Mc
 * style="background-color:#cccccc"|Lv
 * style="background-color:#ffff99"|Ts
 * style="background-color:#c0ffff"|Og
 * colspan="32" |
 * style="background-color:#cccccc"|Nh
 * style="background-color:#cccccc"|Fl
 * style="background-color:#cccccc"|Mc
 * style="background-color:#cccccc"|Lv
 * style="background-color:#ffff99"|Ts
 * style="background-color:#c0ffff"|Og
 * colspan="32" |
 * colspan="32" |

Right, now I'll go to sleep and hopefully wake up to hear your thoughts. ^_^ Double sharp (talk) 01:56, 18 November 2020 (UTC)
 * }

wow
I'm not involved in chemistry or the periodic table or anything similar, tho some relatives of mine including this guy for one, have been. For no good reason i browsed at arbitration request today, including following my way to some long discussions. For what it's worth, i admire numerous comments you made in numbered lists, and your integrity and careful attention paid. It's a shame how "sucky" (technical term) is wp:ANI, and a shame that you've had to spend so much good effort on trying to work stuff out. I hope it does work out well enough for you and other collaborators to keep on developing good content on important topics for the free encyclopedia. And I really enjoyed your quote from Richard Feynman about several men having a discussion, where it seemed particle-guy's point was being lost, but lo and behold the closer of discussion and everyone else had really fully grokked it. Seemed hopeful and relevant to me! Browsing into different areas in Wikipedia is often really absorbing, and I am glad you are contributing. It's unlikely I'll find my way here or to all that stuff again, so just want to say now: you have a fan. cheers, --Doncram (talk) 23:20, 19 November 2020 (UTC)


 * Thank you, reading your note was a pleasant and completely unexpected surprise. The best I can do for family, is that, according to my mother, one of my distant relatives worked with Heike Kamerlingh Onnes, who discovered superconductivity. And my grandmother was an apothecary (in the Netherlands).


 * I appreciate your observation about the numbered notes, my integrity, and attention to detail. The Richard Feynman quote was by anther editor.


 * I have a few irons in the fire, and am looking forward to continuing to attempt to make WP a better encyclopedia.


 * I'll see if can drop by your talk page sometime.


 * Best regards, Sandbh (talk) 03:27, 20 November 2020 (UTC)


 * Hi I was wondering if you felt in a position to support the FAC nomination of nonmetal? Obviously no obligation. It doesn't matter if you've had no involvement in chemistry or the PT. Thank you. Sandbh (talk) 00:57, 16 November 2021 (UTC)

Shared properties of the NNNHNM
At your first bullet states: Let me divide this statement into three parts and comment upon each In summary, I would have to say that this bullet point, if you wish to include it in your list of shared properties of these seven elements, should probably be listed dead last. IMO it is the weakest of your points. YBG (talk) 23:40, 21 November 2020 (UTC)
 * This is of the form "They appear [either] (P1) or (P2) or (P3)", which at face value does not qualify as a shared property, but rather three separate properties each of which is shared by a particular subset of these seven elements. Furthermore, any random set of elements will satisfy this property because every element is either colorless or colored.
 * I'm not sure what you mean here
 * You may mean that those element in this group which are solid under normal conditions are also brittle. If this is your meaning, then this is a shared property only of those element which are normally solid.
 * You may mean that all elements in this group, if cooled until they are solid, are brittle. But this is hardly surprising. I suspect that if cooled to the temperature at which H or N or O solidifies, many if not all elements will be brittle. So while this might be a shared characteristic of these elements, it doesn't seem to be something that distinguishes them from other elements.
 * How is a statement about one particular element germaine to a discussion about the shared properties of seven different elements? Perhaps you are mentioning explaining that you are speaking of one particular allotrope of P, but that is by no means clear from the sentence in its context.
 * You may mean that all elements in this group, if cooled until they are solid, are brittle. But this is hardly surprising. I suspect that if cooled to the temperature at which H or N or O solidifies, many if not all elements will be brittle. So while this might be a shared characteristic of these elements, it doesn't seem to be something that distinguishes them from other elements.
 * How is a statement about one particular element germaine to a discussion about the shared properties of seven different elements? Perhaps you are mentioning explaining that you are speaking of one particular allotrope of P, but that is by no means clear from the sentence in its context.
 * How is a statement about one particular element germaine to a discussion about the shared properties of seven different elements? Perhaps you are mentioning explaining that you are speaking of one particular allotrope of P, but that is by no means clear from the sentence in its context.


 * , thanks, I listed this property first as it's the first thing one notices about the subject nonmetals.


 * 1. The statement that they appear sub-metallic, coloured, or colourless, cannot be applied to any other colour category.


 * To the left are the metalloids, which all have a sub-metallic appearance. To the right are the halogens and noble gases, which appear coloured (F,Cl,Br), sub-metallic (I) or colourless (noble gases). Note that only iodine has a sub-metallic appearance.

So we can see: Sub metallic  Coloured   Colourless Metalloids       6             0          0 SeSPONCH         3             1          3 Halogen NM &     1             3          6


 * In appearance terms, the subject metals are intermediate between the metalloids and the rest of the nonmetals, which is what could be expected given the L-R progression of metallic to nonmetallic character across the PT. There is also increasing metallic character going down each group, which explains the top left to bottom right diagonal occurence of the metalloids.


 * Most elements have a metallic or sub-metallic appearance. A few have a coloured appearance, including e.g. Cu; nine, nonmetals all, are colourless.


 * 2. Yes, that is a good call. I meant to refer to C, P, S, and Se. This is the case for few metals (generally due to the influence of some directional bonding); all metalloids (all having db); four of the subject nonmetals (db); and but one of the halogens (some db). I’ll look at amending the RFC to be more specific on this point.


 * 3. White P, the most unstable form of P, is soft enough to be cut with a knife. Since the properties of all other elements are based on their most stable forms and since black is the most stable from of P, I hope that explains its relevance.


 * 4 Yes, if this shared property was as weak as it looked, then it would've been good practice to place it last.

--- — Preceding unsigned comment added by Sandbh (talk • contribs) 2020-11-22 03:12:33 (UTC)

I still find it extremely odd to tout diversity as a shared property. Diversity may be a property of a group, but to call it a shared property seems weird. It sounds a bit like "What the people in San Seriffe have in common is that they are all either red-headed or right-handed or left-handed". YBG (talk) 04:27, 22 November 2020 (UTC)


 * , I don't find this diversity to be odd, given the seven nonmetals occupy the region between the mystery metalloids (two semimetals; four semiconductors) and the psycho halogen nonmetals (three insulators, one semiconductor).


 * The whole p-block is characterised by its diversity: metals, metalloids, nonmetals, and intermediate types. The PTM can be discerned; as can the metalloids; the halogen nonmetals; and the NG. By default, that leaves the residual p-block nonmetals.


 * The transition metals, to some extent, are comparable in their diversity. There are the active TM in, say, groups 3 and 4; the mainstream TM from, say V to Cu; the schism between the light transition metals and the heavy TM's in periods 5 and 6; the noble TM; Au acting in some respects like a halogen; and Hg a liquid. In some respects, the TM are like a microcosm of the whole periodic table, as noted by Wiberg, which speaks to their diversity. At least they are, so far, all metals.


 * Going back to the residual p-block metals, there is a semimetal (C); two semiconductors (P, Se); one wide band-gap semiconductor (S); and three insulators (H, N, O). S and Se are also photoconductors. You won't find that kind of diversity in any other category.


 * It's reasonable to observe the diversity of these seven; at the same time they're united by their numerous shared attributes.


 * For most of its life the WP PT has had three nonmetal categories. Nothing, it seems to me, merits continuing the two category arrangement, which we only introduced because we couldn't come up with a category name other than other nonmetals. It turns out there are plenty of alternatives in the literature. Of course, the future is a bit out the hands of our project now. Sandbh (talk) 05:13, 22 November 2020 (UTC)


 * How does this seem now? Sandbh (talk) 05:13, 22 November 2020 (UTC)


 * I agree with you that it is not particularly odd to have diversity. I would go further and say that it is not odd to mention or even highlight that diversity. But what I find odd is to call that diversity a shared property', and even more so to list that as the first item on a list of shared properties.
 * I think this is one of those instances where an absurd example might shed some light.
 * Consider the set of elements Be, Si, Cr, Se, Ru, Xe, Gd, Rf, Fl. They include an AEM, a metalloid, a NG, a NNNHNM, three TMs, an La and an Ac. A very diverse set indeed. If you asked me what are the shared characteristics of this set of elements, would you say it is their diversity? If someone said that what unites these elements is their shared characteristics that they are all either a metal or non-metal (unless they are a metalloid or have unknown chemical properties)? That would be a very odd answer indeed.
 * And that is my point. Diversity may indeed be a characteristic of a set, but I think it cannot be a shared characteristic. A shared characteristic is something that is true of each and every one individually, and a single item by definition cannot be diverse (unless, I suppose, if you consider its allotropes).
 * By the way, the set above is not random. There is, in fact, a single defining characteristic that these elements share that no other elements have.
 * YBG (talk) 07:14, 22 November 2020 (UTC)
 * , for that set of elements I probably wouldn't say diversity is a shared attribute since they're scattered across the periodic table. Saying so in that context would be meaningless.


 * OTOH, for the residual nonmetals, they are contiguous in periodic table terms and yet appear to be individually quite diverse. For hydrogen, there are plenty of authors who float it over the middle of the PT, and arguments have been made for placing it near or over B, C or F.


 * I mentioned the diverse appearance of the residual metals, and their variegated electronic structures.


 * The diversity extends to their electrical conductivity, with carbon's exceeding that of some metals, through to those of hydrogen, nitrogen, and oxygen, which are among the lowest.


 * Note how sharply properties change in this part of the periodic table, e.g. from N, a colourless relatively unreactive gas, to P a metallic looking solid (or the well known white or red reactive solids). Or contrast S, a yellow solid, with O, a colourless, gas. This does not happen in other parts of the table.


 * Consider the diversity of the allotropes of carbon (e.g., graphite, diamond, amorphous, fullerene, lonsdaleite); nitrogen (as the pentazonium cation, and predicted to be stable as N6 and N10); oxygen (as ozone), phosphorus (white, red, violet, black, blue), sulfur (too many to list); selenium (metallic, red, amorphous). Even the triatomic form of H makes up most of the universe. This kind of diversity in structural options is not seen in any other category (the metalloids get closest).


 * Perhaps I should say the residual nonmetals are characterised by their diversity and numerous shared properties?


 * Anyhow, I may have fixed this by changing "Shared properties", to "Unique and shared properties". --- Sandbh (talk) 12:51, 22 November 2020 (UTC)


 * A separate point - actually a question. Is there any nonmetal that is neither colored nor colorless? Any element at all?
 * YBG (talk) 07:14, 22 November 2020 (UTC)
 * , under white light, iodine has a sub-metallic appearance. Carbon, phosphorus, and selenium similarly have a metallic appearance. I don’t count metallic or sub-metallic as being “coloured” or “colourless”. Sandbh (talk) 08:31, 22 November 2020 (UTC)
 * OK, I get it. Under this convention, "colored or colorless" is not the equivalent "~p ∨ p" because things having a metallic or sub-metallic appearance are counted as being neither colored nor colorless. Are there other appearances (besides metallic and sub-metallic) reckoned as being not-colored and not-colorless?
 * Being unaware of your convention, I was taking a simple-minded approach based on the WP infoboxes, which state: C is black or clear; P is colourless, waxy white, yellow, scarlet, red, violet, or black; Se is black, red, or gray; and I is metallic gray, or (per the lede) purple-black.
 * YBG (talk) 09:08, 22 November 2020 (UTC)


 * , the purple-black of I refers to its vapour. There is only metallic (e.g. Ag), metallic and coloured (e.g. Au), coloured e.g. (S), and colourless (He). Sub-metallic denotes the element is not as reflective as a metal. Sandbh (talk) 12:51, 22 November 2020 (UTC)

, for the unique properties of H and the group 14–16 nonmetals I compiled the following list. Probably elements in other categories are as unique i.e. the TM, PTM, and metalloids.

H is unique in being the only element having no inner sub-shell.

C is unique in its capacity to catenate. The number of its compounds is so vast and their properties so peculiar that a separate branch of chemistry (organic chemistry) has been developed for their study. Compounds of no other element serve humankind in so many different ways as those of C.

N is unique in (a) the number of binary oxides it forms; and (b) having an electron affinity of approximately zero.

O is unique in that, of the naturally occurring substances necessary to sustain human life, it is taken up and used by organisms in its elemental form, i.e., as an O2 molecule. It is unique as the only elemental gas that is paramagnetic.

P is unique amongst the major biogenic elements in that its elemental cycle excludes a significant volatile phase (although the gas phosphine, PH3, has been recognized as a potential player in the P cycle). P is further unique in that it was first isolated from an animal rather than mineral source.

S is unique in its ability to form a wide range of allotropes, more than any other element in the periodic table.

Se is unique because it is folded into its protein while the protein molecule is still being made. All other trace elements are added to their respective protein molecules after the cell has finished synthesizing the protein. Sandbh (talk) 11:40, 30 November 2020 (UTC)
 * Re inner subshells: what about He though? Or is it about how they are unique in the category alone? Double sharp (talk) 22:06, 30 November 2020 (UTC)


 * A list of unique properties is interesting, but doesn't help establish the shared properties of the NNNHNM. YBG (talk) 01:36, 1 December 2020 (UTC)

, for He, I understand its two electrons shield each another, to some degree. That is not the case for H. Sandbh (talk) 05:25, 16 December 2020 (UTC)

regarding high school students being taught about semiconductors
In fact, it does not seem to be on UK high school syllabi if Chemguide is anything to go by.

P.S. Sb does not seem to have a stable semiconducting form. Double sharp (talk) 14:58, 25 November 2020 (UTC)


 * , thanks for that.


 * Teaching semiconductors in high school
 * Some examples:


 * Fundamentals of senior chemistry, Heinemann Educational Australia, 1982: "Why study chemistry at high school(?)…Si and Ge have lustre and are semiconductors but their chemical properties are more typical of nonmetals."


 * High school chemistry unlocked, Random House Children's Books, 2016: "Many metalloids are used as the basis for semiconductors…".


 * Chemistry for high school, Rex Book Store, Manila, 1999: "The conductivity of semiconductors generally increaşes as the temperature is raised, which is opposite to the behavior of metals . Impurity doped germanium and silicon act as semiconductors."


 * Must know high school chemistry, McGraw Hill Professional, 2019: "The elements in this area (B, Si, Ge, As, Sb, Te, At) are the metalloids. Some have unusual electrical properties that make them valuable in the computer and semiconductor industry."


 * Semiconductor facts for kids, Kids Encyclopedia Facts, 2020: "A semiconductor is a material that in some cases will conduct electricity but not in others…Semiconductors are the foundation of modern electronics…Kiddle educational articles are based on selected content and facts from Wikipedia, rewritten for children and primary / elementary school students."


 * Semiconducting Sb
 * Black antimony is stable enough to be used in bolometers (1956):.
 * Our own entry on black Sb says, "At 100 °C, it gradually transforms into the stable form. The yellow allotrope of antimony is the most unstable."
 * The Nature Chemistry article on antimony says, "A metalloid, rather than a true metal, antimony exists in four allotropes: the most stable is metallic and grey; with a non-metallic yellow, a black and an explosive white form also known."
 * Their article on polonium quotes the Curie's from 1898: "We believe that the substance we recovered from pitchblende contains a heretofore unknown metal, similar to bismuth in its analytical properties. If the existence of this new metal is confirmed, we propose that it be named polonium in honour of the native land of one of us.”
 * How cool were the Curies? They picked it over 120 years ago!
 * The Feb 2013 Nature Chemistry article on astatine, pre- the Sep 2013 announcement by Hermann et al., has the usual textbook error: "Even its colour is unknown; based on increasingly dark colours for halogens from fluorine to iodine, however, black seems a logical guess."


 * Preliminary observations


 * 1) High school students are taught about semiconductors.
 * 2) "Describing the intermediate elements as metalloids is clearly in fashion today." (Goldsmith, 1982)
 * 3) All known metalloids are (semimetals or) semiconductors, or exist in semiconducting forms.
 * 4) Rayner-Canham regards Sb as a metal but, curiously, does not explain his rationale.
 * 5) The properties of Po are consistent with the Curie's regarding it as a metal.


 * Are we able to agree on these? Sandbh (talk) 23:38, 25 November 2020 (UTC)
 * No, I don't think we can for all of them.
 * I was talking about the mechanism by which semiconductors conduct electricity. Unlike those for metals and semimetals (which is just metallic bonding leading to mobile electrons), and insulators (which don't conduct significantly due to a lack of mobile charge carriers), the semiconductor mechanism does not seem to be part of most high-school chemistry syllabi. Naturally, the name and the fact that Si is one may easily be thrown around, but I do not consider that to "count". Surely every high-schooler sees the superheavy elements on his or her periodic table, but that does not make them a high-school topic.
 * According to Holleman & Wiberg (p. 758), black antimony starts to transform into the metallic allotrope already at 0 °C. I doubt that could be considered particularly stable. If that's enough to disqualify antimony, though, shouldn't tin be worried because of the grey allotrope? White tin starts turning into grey tin below 13.2 °C already.
 * A metalloid category is certainly common, and I am not proposing we get rid of it on WP. There is simply disagreement between sources about its boundaries. It is true that if writing a chemistry article or book off-WP, I would not use the term and prefer to speak only of metals and nonmetals, but that is different.
 * Whether all known metalloids are semimetals or semiconductors or exist in semiconducting forms depends very much on which elements an author considers to be metalloids, on which there is not agreement. In any case, there are certainly elements that exist in semiconducting forms but which are rarely considered metalloids (iodine springs to mind).
 * R-C explains it in the article of his that you sent me, referring to Hawkes who notes that it's only B, Si, Ge, As, and Te (not Sb) whose conductivities fall in the gap between clear metals and clear nonmetals. That being said, he is one author and others disagree. Just like how others disagree with calling Po or At metals, though.
 * I actually agree that Po is better considered a metal. Same for At. And, although you probably disagree with that one, the same for Sb. And I would do all that if writing a chemistry article or book off-WP. But, that's not what I feel should be the basis of what WP shows. Given that there is scientific disagreement, both between you and me, and within the literature, I feel that arguing based on science for WP is never going to give any reasonable resolution until the literature develops some kind of consensus. I already explained on YBG's talk page. I think there's no point continuing this because it'll go over the same thing again and again; the community will decide it when I put up the 2010 scheme for an RFC.
 * Double sharp (talk) 23:55, 25 November 2020 (UTC)

Regarding metallic lustres
You may like Metallium's photo gallery of the elements (plus some extra photos). I think you might see what I, following DA, am getting at when I say that Ge does not have a really metallic lustre. Compare:
 * True metallic lustre: Ga, In, Sn, grey Sb, Bi, Po (different site)
 * Glassy, "metalloid" lustre: Si, Ge, black As (different site), Se, Te (different site)

I couldn't find a good picture of black Sb, raising suspicions in me that H&W are right and that it is really quite unstable. Double sharp (talk) 09:58, 26 November 2020 (UTC)


 * , Rochow discussed the optical properties of the metalloids in his 1966 book. He gave the following reflectivity values: Diamond 6%; Si 41; Ge 35; As 46; Sb 70; Te 59. Sandbh (talk) 10:23, 26 November 2020 (UTC)
 * Yup, and notice how high Sb is compared to everyone else! ^_^ Does he give values for Sn and Bi? (And although that is probably difficult, Po?) Double sharp (talk) 11:22, 26 November 2020 (UTC)

From the second link with extra photos are some more rods: Au, Pt, Pd, Ir, Ru, Sn, Sb, Bi. Here Sb does not seem to look visibly distinguishable from any other metal. Ge, however, is further up the page and looks very distinct. Double sharp (talk) 21:42, 26 November 2020 (UTC)

Copying licensed material requires attribution
Hi. I see in a recent addition to Periodic table you included material from a webpage that is available under a compatible Creative Commons Licence. That's okay, but you have to give attribution so that our readers are made aware that you copied the prose rather than wrote it yourself. I've added the attribution for this particular instance. Please make sure that you follow this licensing requirement when copying from compatibly-licensed material in the future. — Diannaa (talk) 13:59, 4 December 2020 (UTC)


 * Thank you. I wrote that text myself (as the author of cited article). Is an attribution required in this case? Sandbh (talk) 03:42, 5 December 2020 (UTC)
 * Yes I think you should, because patrollers won't know that.— Diannaa (talk) 12:47, 5 December 2020 (UTC)

Regarding goodness-of-fit values
Interesting, so it is towards higher-degree polynomials (which degree?). So it's not as bad as I was worried about, even though because of even-odd periodicity I have to wonder if polynomials may undersell the goodness of a trend like B-Al-Ga (3d insert)-In-Tl (4f insert). But something I'm wondering according to your analysis: how does Ti-Zr-Ce-Th compare to Ti-Zr-Hf-Rf? Reason being that the other d block trends are all like Ti-Zr-Hf, V-Nb-Ta, etc. with the kink. If they show worse goodness-of-fit values than the Sc-Y-La-like Ti-Zr-Ce, V-Nb-Pr, Cr-Mo-Nd, then I think it is suggestive.

Not that it really proves anything, because a Lu supporter like me can always say "of course group 3 should follow the group 4 trend, they are both d block", and a La supporter like you can always say "of course group 3 should follow the group 2 trend, because the Ln contraction should come only after group 3". So it becomes like Jensen's 1982 arguments: they are only persuasive if you already have determined where the f block is inserted, and otherwise are not definitive. That's why as you know I consider the thing settled by Jensen 2017 rather than Jensen 1982.

I also think it should be pointed out that among people who have views on this, some consider the thing ultimately settleable by one answer (me, Scerri), and some consider that different versions will always have their places (like you). I guess, partly it is a matter of how people feel physics and chemistry should be reflected on the PT: if you feel they are both relevant, then maybe you want to move elements around to create different versions, but if you feel that the physics in terms of the electronic structure is supposed to be explaining the chemistry, then you'll probably want only one version. Therefore I am not sure your proposed IUPAC guidance will satisfy people.

Also, I rather suspect that if Scerri is actually writing an article summarising the conclusions, it's likely that the six project members have managed to agree on something. But we'll see.

(Left off the ELEM talk page because this is getting a bit FORUM-y, I think.) Double sharp (talk) 02:02, 8 December 2020 (UTC)


 * 2nd degree polynomials, in all cased. On group 4 I only looked at C-Pb, and C-Si-Ti-Zr-Hf. I can look at Ce-Th too; that would be interesting.


 * Yes, I know about Scerri's view. AFAIK he has never looked at the way I've done it, which takes a leaf out of G&E. I suppose it's never occurred to anyone to extend it to group 2 and group 4. Sandbh (talk) 02:27, 8 December 2020 (UTC)
 * Similar figures appear for group II in Jensen (p. 956 of this paper) and for group IV in G&E (2nd ed., p. 957). So I wouldn't say no one's extended the idea. Actually I kind of think that in some sense just about anybody who's used A and B group numbers or an 8 column periodic table is looking at it this way or is at least close.
 * I worry that 2nd degree polynomials may be inadequate for a trend with two kinks like B-Al-Ga-In-Tl (kink at Ga and then in Tl). 4th degree might fit better except that it would probably be too easy to fit anything then. Double sharp (talk) 02:40, 8 December 2020 (UTC)
 * (Now that I'm not quite as sleep-deprived as that day; of course it would be too easy, it's five points with a 4th degree polynomial, and can always be fit perfectly.) Double sharp (talk) 07:00, 13 December 2020 (UTC)

Hmm. For group 4, the figures are C−Pb = 0.69; C−Hf = 0.71, so nothing effectively there. For C-Si-Ti-Zr-Ce-Th it's 0.81! I can sort of see an argument here for C-Si over Ti-Zr, and then splitting the f-block so that Ce-Th are under Zr. So the sp block has equal halves, as Scerri once supported.

I hesitate since I'm OK with B-Al- over Sc-Y-La, since there's barely any TM chemistry here, whereas with C-Si-Ti-Zr-Ce-Th and Ti3+ and Ce3+ I think the different kinds of chemistry become too scrambled. Sandbh (talk) 03:35, 8 December 2020 (UTC)
 * Well, if one wants to justify it, one could say that boron and carbon are certainly not stuck in their group oxidation states, but show many lower ones as well. OTOH, any thoughts of ionicity for them are basically fantasies, so the oxidation states may be too formal to really use here. I kind of wonder how N-P-V-Nb-Pr-Pa looks compared to N-P-As-Sb-Bi-Mc, continuing the march towards the right. I somewhat suspect that what's going on is that your measure is still somehow overly favouring linearity (a parabola can well approximate a line if needed, but it can't really approximate a kinked trend like B-Al-Ga-In-Tl that looks more like a quartic if anything), which is why the "no block insertions" trends are getting overly high values.
 * Anyway, I think this comes back to my usual response: "if the argument gives us something bad if we apply it where we're sure of the answer, then why should I have faith that it'd apply when we're not sure of it"? I think we agree (correct me if I'm wrong) that whatever thing one wants to use as one's PT basis in one's context, one ought to apply it consistently. That basically explains why I'm in the "physics only" camp: I'm not seeing any way one can apply chemistry consistently, because it's too fractally complicated with trends and then exceptions to the trends and then exceptions to the exceptions. That's why I favour the physics-only He-Be + Sc-Y-Lu table, because it's consistent and I don't see any other way to be consistent: the fuzziness of chemistry I prefer to leave for the fuzziness of categorisation. You could say maybe that I'd be willing to accept a consistent "max out physics" = He-Be + Sc-Y-Lu table as well as a consistent "max out chemistry" table as two fundamentally correct representations, but with the problem that I have serious doubts that the second can even exist. So, that's why I think there's only one. But you can see that there's a window of possibly changing my mind. ;) Double sharp (talk) 03:42, 8 December 2020 (UTC)

Yes, agree 100% ^_^ They each have value, in their contexts. A better chemist bears in mind both options at the same time, rather than one or the other. The chemistry one will always be fuzzy, unless we ever get to a day where chemistry becomes 100% reducible to physics. Might need a brain the size of a planet to do that one though.

I'll have a look at group 5 and 15. Black P might be hard to get good values for. Sandbh (talk) 06:09, 8 December 2020 (UTC)


 * Group 5 as N-P-V-Nb-Pr-Pa = 0.71; group 15 as N-P-As-Sb-Bi = 0.81; Group 5 as N-P-V-Nb-Ta = 0.90. Sandbh (talk) 07:16, 8 December 2020 (UTC)
 * OK, interesting. I think we're not really in that much disagreement about this idea; I do agree that a better chemist can understand all options. I think where we differ is whether we think they should be reflected on the PT generally, really. I could see relationships like B-Al-Sc or Be-Mg-Zn or Sc-Y-La maybe as special illustrations when something needs to be emphasised, but because of the consistency issue, I think I would prefer something along the lines of 8 column periodic table or Bayley pyramid or parenthesised pseudohomologues to show the secondary relationships. But I generally feel that the strict-physics He-Be + Sc-Y-Lu table is best at consistency, best at pedagogy, and best at the most general case when you aren't trying to make any chemical point and just need to show a PT for a general context. But YMMV; after all, the greatest benefit of this sort of thing is making it clear what both of us really think and sharpening it, I guess. Double sharp (talk) 10:19, 8 December 2020 (UTC)

P.S. I also think the 1-18 finger-count group labels suck. I think you also know the ones I like. But if not, you can see them at User:Double sharp/Template Periodic table as usual. They are something like those of the Marks brothers' Newlands Revisited but a bit different, and are sort of an attempt to make sure the secondary chemical relationships are not lost: going B-Al-Sc-Y-La-Ac, we go from groups IIIp to IIId to IIIf rather than 13 to 3 to unnumbered. Just for fun of course. Double sharp (talk) 10:28, 8 December 2020 (UTC)

Short question
If you're in favour of chemistry as a possible organisational principle for the PT (whence B-Al-Sc-Y-La), then how do you justify Og under Rn? It is an extraordinarily poor match there in properties and in continuing group trends, being rather similar maybe to Si or Sn. (In fact, the end of the 7th period gives much better chemical congeners if it goes Mt-Ds-Rg-Fl-Ts-Og-Mc-Lv-Nh-Cn. YMMV on whether that is acceptable given how much it scrambles the atomic numbers.) Likewise, how do you justify U under Nd rather than under W? U under Nd is mostly nonsense if we think of chemically similar elements as belonging together; it only makes sense from a physics POV. Do you have some way to deal with these, or would you advocate moving them too? Double sharp (talk) 14:15, 8 December 2020 (UTC)


 * , Eric has written about the possible end of the periodic table and periodic trends in period 7. And there are probably some relativistic perturbations in e.g. Cn and Og. I don't worry about these so much since we can explain what is going on, and there are relativistic phenomena elsewhere in the table.


 * The common form of the periodic table is mostly chemistry-based but it does make some concessions to electronics/physics.


 * On the early An, Wiberg (p. 1720) says:


 * "Th, Pa and U display redox behaviour similar to that of the TM Hf, Ta, and W, and for this reason, the An were at one time placed in transition groups IV, V and VI. However, the spectroscopically determined structure of their electron shells, as well as many of their physical and chemical properties (see below), show they do actually belong in the An group. The similarities in redox behaviour of An and TM progressively disappear when moving in the direction Np, Pu, Am. However similarities in redox behaviour between An and Ln first appear with the heavier AN from Cm onwards."


 * I recall reading somewhere that PT trends are vertical in groups 1−2; start becoming diagonal in the p-block; are horizontal along the 3d metals, vertical along the heavy TM; and horizontal along the An and Ln, with the early An midway between the d-block and and the f-block.


 * For Nd and U, I guess the lack of a good vertical trend is not so relevant, given my preceding paras. There is a resemblance between La-Ac; Ce-Th; and Pr-Pa. By the time we get to Nd-U the resemblance has nearly gone (the best Nd can so far do is +4). Restrepo says, "Mathematical and computational tools estimate that the number of energetically stable chemical compounds is greater than 1060, which is called the chemical space." Eugen says, "chemists have so far explored only a completely negligible fraction of this chemical space!!". So who knows, if we can get Pr to +5 maybe one day we can coax Nd to +5 or even +6. --- Sandbh (talk) 01:25, 10 December 2020 (UTC)
 * Hmm. Is the common PT mostly chemistry-based? OK, we can agree I think that a physics table is He-Be + Sc-Y-Lu, right? Then it seems to me that the common form of the PT (He-Ne + Sc-Y-La) has 115 elements placed according to physics and 3 elements placed against it (He, Sc, Y). Seems lopsided the other way if you ask me. I think we can agree though that the PT is slightly poorer for not being consistently one way or the other, though.
 * I agree that we have not explored most of the chemical space. But I think we can legitimately say that chemists have explored most of the easily accessible parts of it. That is, we have at least explored most of the representative chemistry of the elements, that are naturally shown without us trying to force things; and what remains requires more effort.
 * I think what you say about we can explain what is going on is pretty much why I favour the physics table. Because it's not a zero-sum game: by going to physics, you don't necessarily go against chemistry. Rather, the physics enriches the chemistry by helping to explain it. To put it another way: you don't lose the Sc-Y-La relationship if you decide to go for a physics table and show Sc-Y-Lu first, because no one can take away the fact that Sc-Y-La are all three electrons above the noble gas, and it is still shown by the fact that each of those elements is the third element from the start of the row. Same with B-Al-Sc for that matter. The physics just explains why you see the trends you see: Sc-Y-La has a s-like smooth trend, because there is no insertion of a block to be involved, whereas Sc-Y-Lu has a d-like trend with the first element (Sc) a bit different from the similar other three (Y, Lu, Lr). You just have to accept that what is shown as a vertical relationship may not always be the closest chemical relationship – but we already understand this: as you said, PT trends are only consistently best as vertical in the s block. Elsewhere they may not be. So I would say: He-Be + Sc-Y-Lu is not only a physics/electronic table. Rather it is a table where physics/electronic is enlisted to explain chemistry, and therefore unites both physics and chemistry. Even though physics does not explain all of chemistry yet, if we limit ourselves to chemical periodicity, it explains enough already for general use.
 * Which loops back to my first point: B-Al-Ga is nearly universally accepted by now, even though anyone can look and see that Al-Sc is often significantly closer than Al-Ga. So, small differences in chemistry are not really worried about in these cases if the physics dictates a placement: I think we can both agree that Al and Ga do share many things in common. We also know that the La table first came about because of a misunderstanding of electron configurations: firstly the configuration of La, [Xe]5d16s2, was misinterpreted as implying that no 4f involvement could be had from it, and then because of faulty configurations Yb-Lu was thought to add the last 4f electron implying that Lu ended the f block. Now we know both are wrong, but because the result doesn't look too horrible chemically, most people didn't bother changing it. But the point I'm making from it is that Sc-Y-La came about from physical considerations too: sure, they were wrongly interpreted and based on wrong data, but the argument was a physics one rather than a chemistry one. Therefore, I rather suspect that if IUPAC recommends Sc-Y-Lu, the majority of chemists are not going to make a fuss over it, just like they didn't for B-Al-Ga: I think we can both agree that Y and Lu do share many things in common. (They are both rare earths after all.) But if they don't, then for sure those who think from physics are going to complain. Which for me is maybe the sociological argument for Sc-Y-Lu: the only way the dispute will ever die out is if Sc-Y-Lu gets accepted. From just chemical taxonomy, neither Sc-Y-La nor Sc-Y-Lu is less than useful, so no one will make a fuss. From physics explanations, Sc-Y-La is absolutely less than useful, so people will make a fuss. Therefore what presumably will end up eventually happening is that physicists, and chemists who prefer to think physically, keep on arguing for decades and decades in favour of Sc-Y-Lu and eventually win because the "silent majority" is not really favouring La; it just does not care. Double sharp (talk) 02:38, 10 December 2020 (UTC)


 * I think the only thing worth agreeing on is the idealised blocks table with He over Be and Lu in group 3. Disagreeing on anything after that is a non-disagreement, since each variant is good for its particular purposes. The form used within IUPAC is customised in the direction of chemistry, with He over Ne, and 15 Ln and An (but still with a tip of the hat to physics, with B-Al- over Ga). For a chemistry body that's understandable, and I could understand their reluctance to recommend any particular form. If IUPAP had an internal PT that ought to be He over Be and Lu in group 3. After that it's up to the chemistry community as to which form becomes the most popular. I'll have to back and read Eric's 2020 article about recent attempts to change the PT, and his rationale for Lu. Sandbh (talk) 03:36, 10 December 2020 (UTC)
 * Well perhaps my He-Be + Sc-Y-Lu view (for chemistry even) is partially guided by my personal preferences in pedagogy. I find it a lot easier to motivate periodicity from the physics rather than to do "stamp collecting", but perhaps for others that is not so. Let's say it is the mathematician's prejudice. ;) Leaving aside disagreements on whether it is best to illustrate other periodic trends by changing elements or not (I think it might cause some pedagogical confusion but I can simultaneously see the visual appeal), I kind of feel however that if you're just introducing the PT as an organisational tool, without having any purpose beyond that at emphasising some particular trend, the "blocks PT" is still probably best as something to start from and deform at will.
 * Seems to me Scerri's 2020 article makes his usual rationale for Lu. He argues that we should keep in mind the 32 column form (fine), keep Z in increasing order (fine), not split the d block (umm), and keep the block sizes in accordance with how big QM says they should be (so no 15-element footnotes). Well, my opinion on this is basically that: from a physics perspective, this is not a totally satisfactory argument because the blocks are not defined, but since defining them physically naturally leads to the conclusion against a split d block we can chalk it up as "incomplete, but completes to a correct argument". From the perspective of the final chemistry, the blocks are not important, but Lu and La are not too chemically distinct, so this perspective says "who cares". From the perspective of pedagogy, then since trends across blocks match each other better with a Lu table and without a split d block, this argument works fine: the Lu table is easier to learn how to use. Therefore, even though I think the really definitive argument is searching for 4f involvement and finding it only in La but not Lu, I won't be disappointed if IUPAC decides on the Lu form on this basis. Double sharp (talk) 03:52, 10 December 2020 (UTC)
 * Yes, re-reading his article now, it strikes me as being circular-ish. He says there is no optimal table, and the choice is interest contingent. Then he plugs for Lu in 3, on the basis of four grounds of interest:


 * "First, it unifies all the elements together by including the f-block. Second, it displays all the elements in order of increasing atomic number. Third, it avoids splitting the d-block into two highly uneven portions and fourth, it depicts all the blocks of the periodic table in accordance with the underlying quantum mechanical account of the periodic table which calls for 2,6,10 and 14 electrons to occur in various electron sub-shells. If one insists on retaining an 18-column format, we recommend that it should be the version shown in figure 4 which benefits from the insight afforded by the equivalent 32-column table, namely figure 10."


 * This is a weak position. In the 18-column form argument 1 is irrelevant. Argument 2 applies in the 18-column La form. Argument three has no basis in science. Argument 4 is somewhat relevant. Arguably, what Christie and Christie (2000, p. 42) said is still the case: "chemistry rests much more strongly on its…foundations of the 19th century and earlier, and much less on the insights of modern quantum physics. This may change if chemistry can be reduced to physics.


 * It's no better than whatever prompted the internal IUPAC form. Sandbh (talk) 04:10, 10 December 2020 (UTC)
 * To be honest, even as a Lu partisan, my general impression of most of the Lu-supporting papers around is that they are right for the wrong reasons. That is, I feel that their conclusions are correct, but I cannot support the way they get there as definitive. Sometimes they are only suggestive and sometimes I feel they just don't work. And my impression of some parts of your La paper (not all of it) is that it is wrong for the right reasons. I feel your conclusion is not correct, but I think that you are on the mark in some ways, such as when you talk about symmetry not being a valid decider by itself. Hopefully to be taken as half-joking. ;)
 * What's really funny though is that the early physics papers on the La-Lu issue present a much stronger position. Their arguments basically boil down to the one DA and I have been advocating here: "La-Yb use 4f orbitals, Lu doesn't". If you look at Hamilton's 1965 original paper you will notice that nearly all his arguments are about this 4f involvement. The exceptions are superconductivity – which Mathias and Wittig later related to 4f involvement in La anyway, so it's not an exception – and in one paragraph a few rattled-off properties along the lines of Jensen's article, which Hamilton calls "unsophisticated" before moving on to his 4f arguments. This is literally the only argument I've seen that seems decisive by itself, provided the definition of block implicit in it is accepted, which I feel can be given a pass because it seems natural to ask for f elements to use f orbitals. And maybe that is confirmed in the sense that this is the one Hamilton and Wittig ran with! So the mystery is why the single strong and deciding argument has not been seized on: maybe it and its importance was not understood well enough. Or maybe no one could stomach it because they realised that consistently applying it means helium most go over beryllium, who knows. Instead we had a falling down to circular ones and just plain cosmetic ones in the end. Of all the six on the project, judging from their writings, I feel that Jensen is closest to a good view on the matter because he at least presents the 4f argument in his writings. I am not too thrilled about all the other arguments he bundles it with, though. I think those other Jensen arguments confirm that Lu gives internally consistent chemical and physical trends, but do not succeed at proving that Lu is correct (see the next section for why). Scerri's view we've seen above, I haven't seen Ball and Ohrstrom really tackle the issue in depth in their articles on it, Restrepo's is inconclusive because we all know the most similar element is not always the one placed below, and Lavelle is only looking at the ground-state configurations (in this case Jensen is right on the mark when he points out that you have to look at excited states, because that is the 4f argument).
 * As I said, I will not be disappointed if Lu is chosen for the reasons Scerri gives, mostly because it is nothing new for valid scientific advances to make it for the wrong reasons. That seems to be more or less exactly what happened with heliocentrism vs geocentrism, which is an analogy you will recall DA and I have used for this issue. It should also be noted that heliocentrism over geocentrism was largely agreed between scientists even before Newton provided the theoretical framework and physical justification, so even if you think physics has not adequately explained chemistry, it would be nothing new. (I agree that it has not, but contend that when it comes to the specific subject of periodicity, it has done enough.) So even though it may be to me scientifically half-disappointing (in terms of the way in which the conclusion is reached, not the conclusion itself), sociologically I will be totally unsurprised. Double sharp (talk) 05:22, 10 December 2020 (UTC)

Yes, it seems to me that the current situation arose as a result of historical accidents; the obscurity of La and Lu chemistry; and the lack of an aficionado of periodic table history of the calibre of such as Scerri. As well, and as you allude to, many of the arguments one way or the other were poorly thought out or presented. I see that a lot in the research literature with complaints about poorly designed studies. A byproduct of publish or be damned, or, never mind the quality, feel the width.

I have a bias against simple solutions; symmetry; and consistency, since chemistry---based on my readings---is full of subtleties, inconsistencies, and weird things that happen in the margins. The texture of the world, as I’ve referred to it as. Characteristic I supposed of a discipline that has not been reduced to physics.

My impression is that the arguments about f-involvement in La and no such involvement in Lu are questionable since, although I haven’t been delving into this too deeply, the full f-shell in Lu does influence its properties.

I won’t mind what Eric's project comes up with, or what IUPAC does with the report, given some of IUPAC’s bizarre recommendations, since each option, even the IUPAC form, has its context. If Lu rises to the top of the heap, so be it. --- Sandbh (talk) 06:03, 10 December 2020 (UTC)
 * My impression is that the arguments about f-involvement in La and no such involvement in Lu are questionable since, although I haven’t been delving into this too deeply, the full f-shell in Lu does influence its properties. – only to a similar extent as Hf. In other words, La-Yb have direct usage of the 4f shell for bonding; 4f has influence from Lu-Rn, but it is only the incomplete shielding effect, similar to 3d from Ga-Kr. The bonding orbitals for Lu are only 5d, 6s, 6p. So no, this argument is not questionable: it can be and has been calculated, and when that is done, it becomes decisive. (Provided of course that you accept its premise. The cost is accepting helium over beryllium, it should be noted.) It is true however that these arguments (which fix information about lack of Lu 4f involvement, presence of Zn 3d involvement, and so on) are difficult to use and understand due to the need for rigorous quantum mechanical calculations to justify them, which probably accounts for their lack of prominence: one must scour the computational chemistry literature to use them effectively without misunderstandings, and one has to have some sort of knowledge of how things work there to avoid misreading the papers (there are some local terminology uses). If not for DA (a computational chemist, as you remember) I could not have. So, I think you have the wrong impression based on not having delved into it deeply enough. Nothing wrong with that; so did I before DA explained it to me. Even now I don't understand the chemistry involved in how they get to their conclusion; I just know enough to be able to read their conclusion correctly.
 * Presumably this is also exactly what happened about the sideline of condensed-phase configurations, which Scerri talked about based on Schwarz's article. He called them condensed-phase configurations. In actual fact, Schwarz was not talking about the configuration in the metal, which is what is usually meant by the words "condensed-phase configuration", but about configuration state-averages of neutral free atoms. The configuration of the metal is in fact not well-described by integer occupancy and can only be well-described by averages: Cu metal is about 90% d10s1, 10% d9s2. In fact, visible light is usually enough to change the averages for the TMs, and they often flow continuously through different configurations when this is done (cite). So in a roundabout way, what happened when I first convinced you to the La form was that because of this terminological confusion, I looked up old information (before this flowing was known, apparently) about the condensed-phase configurations of the Ln and An, and based on wrong data was convinced to La. (Which would have been correct if the data had actually been correct, which it wasn't.) I think this underscores the need to have an expert who understands the terminological uses present.
 * Well, you know I differ with you about "each option has its context". So let's leave it at that. Simple solutions and symmetry are for me not requirements, but not something to be suspicious of either. If they're there, they're there, and if they're not here, they're not there. However I have a nagging feeling that consistency may be underrated among chemists for the PT (a sentiment echoed by Jensen) for the reason that it's pretty obvious that it would start demanding helium over beryllium. Some chemists do indeed draw from this the conclusion that that placement is right (Kurushkin), but most would probably rather retreat away from it. I feel that Kurushkin has gotten it right, but also that he's going to have a hard time persuading people until helium chemistry blossoms. In any case, I'll reserve judgement on the IUPAC project till its results come up, but as you know I have a strong suspicion based on Scerri's comments at the Zoom workshop that indeed Lu will be the outcome. Which will, of course, make me happy enough, as I feel that scientifically speaking this should have already been settled by the physics papers of the 1960s and 1970s. I also do suspect that I will not be too satisfied with the rationale used to justify that outcome, though.
 * In any case, it seems that physicists and IUPAP are getting somewhat fed up with IUPAC's custodianship of the periodic table. That's because the way the PT usually changes now is to add new superheavies, for which it's obvious that physicists and not chemists have the expertise, and the JWP reports that legitimised elements 113, 115, 117, and 118 were...scientifically not the best. (The conclusions were probably all right; the way they got there, not so much. Sounds familiar?) If these tensions go far that the significant physicist view that IUPAC should no longer play a role in this process eventually becomes reality, we may indeed end up with the PT being taken over by physicists. Which is an outcome I'm of course entirely in favour of. ;) Double sharp (talk) 08:54, 10 December 2020 (UTC)

The IUPAP minutes say, "Cecilia, and many others, are of the opinion that there should no longer be a role for IUPAC in the validation and naming of new super heavy elements, given the central role played by nuclear physics in the synthesis (or discovery) of the new elements." There is nothing there about IUPAP/the physicists taking over the PT. Pardon my scepticism that this would ever happen. Sandbh (talk) 05:05, 16 December 2020 (UTC)

Comments on Jensen 2017
Please note, I don't agree with everything Jensen said. In fact I agree with you that the 1982 paper doesn't really prove anything much from most of its arguments because of a circularity problem: it amounts to saying Sc-Y-Lu is better because it better matches the other d block groups, but asking for that implies you think the f block goes before group 3 and doesn't interrupt the d block, which implies you already think Sc-Y-Lu is better. What I think however is that the 2017 sentence I quoted from him is, as you put it, a key observation. I also think it is the categorical argument that settles it: I guess for you it might not, but maybe you could agree that it settles it from a physics point of view (or maybe for you within an electronic/physics context). Lu and Lr are in the d block, because they cannot use f orbitals as valence orbitals; La and Ac are in the f block, because they can. (As shown in 10.1364/JOSA.61.001112, the 4f→5d promotion energy of Yb is higher than that of the 5d→4f promotion energy for La, and the 5f→6d promotion energy of No is higher than that of the 6d→5f promotion energy for Ac. So the f orbitals in La and Ac are more chemically available than the d orbitals of Yb and No, which we already know are chemically available.) To some extent I think the original sin here is not defining what a block is, but since the definition his 2017 paper seems to be implying (that f elements ought to somehow use f orbitals for chemistry) seems particularly natural, I will give that a pass. Note also, this is not a symmetry-based argument, despite its symmetrical result.

On whether the PT is an electron configuration table: clearly it is not (whether ground-state or idealised), because He-Ne. But neither is it a chemistry table either clearly, because H-Li, and indeed because Rn-Og, and because Nd-U, and because N and Bi in the same group. In fact, I would agree with you that the traditional forms are basically just inconsistent and cannot decide what they are supposed to be based on, as Kurushkin complained about. And from the fact that most chemists don't seem to bat an eyelid about this, I rather suspect that the foundations of the PT are just annoyingly poorly documented as standard notions: no wonder writing the PT article is so hard, when nobody is defining what a block is ("I know it when I see it" is not convincing when you literally have an argument in the middle of the table on group 3), and nobody is sure about the relative roles of chemistry vs physics when deciding PT placements. Maybe this will change because IUPAC will probably have to deal with this issue when its task force decides what it's going to recommend, but even then it will probably be slow since the average chemist's reaction to He-Be is probably just incredulous. Jensen said it was an idealised electron configuration table here (so it's not a ground-state one, which is what I think he was complaining about based on this): I think that's what it should be, because nothing else really works with consistency and explains so much rather than just documenting it, but as long as He-Ne is there I do not think it can legitimately be said that that is what it is. Ultimately, I suspect that waiting for IUPAC is the best bet here, because whatever they do, some air will be cleared out wrt how these issues deal with Sc-Y-La. Maybe pencil in the helium issue sometime before the end of this century. I am sure the element can wait, it is really 13.7 billion years old after all. ;) Double sharp (talk) 14:48, 8 December 2020 (UTC)

P.S. Jensen 2015
Strangely enough, in his response to Lavelle, Jensen gets it in the right order.

Slightly more than 32 years ago I published an article in the Journal of Chemical Education entitled “The Positions of Lanthanum (Actinium) and Lutetium (Lawrencium) in the Periodic Table” in which I called attention to the fact that, based solely on their groundstate, outer (n-1)d1ns2 valence configurations, both La and Lu (and by implication their heavier analogs, Ac and Lr) had equal claim to placement in Group 3 of the d-block below Sc and Y (1). Since both La and Ac also had low-lying empty f-orbitals, whereas Lu and Lr did not, this fact alone strongly suggested that the former two elements had, like almost a quarter of the other d- and f-block elements, irregular configurations and should therefore be assigned to the first group of the f-block as idealized (n-2)f1ns2 elements, whereas Lu and Lr, for which this option did not exist, should be assigned instead to the first group of the d-block below Sc and Y.

To further support this conclusion, I compared groups trends in such properties as atomic radii, ionization energies, melting points, and electronegativity values for the alternative sequences Sc-Y-La versus Sc-Y-Lu with the corresponding group trends for the other members of the d-block and showed that the latter, rather than the former, choice gave the best fit. Yet further evidence for this choice came from a comparison of the structures of metallic La versus metallic Lu with the structures of metallic Sc and Y, the structures of their oxides and chlorides, their superconductivities, the structures of their conduction bands, and their behavior during fractional crystallization. Once again all of these properties favored the placement of Lu rather than La (and by implication Lr rather than Ac) in the positions below Sc and Y in the periodic table.

This is precisely the convincing order. First the f block is established as La-Yb / Ac-No according to the f-orbitals argument that DA and I have been using. Then the group trends are only there to further support the conclusion and show that it is internally consistent; they are just there to support a conclusion that has already been made. When used that way, they actually work.

Judging by this, I have to say that this supports my stand that out of the writings of the six IUPAC project members, Jensen's are the best in terms of convincingness and deep understanding of the situation. In fact it makes me think even more highly of his stand and understanding of the f block situation. The expression of his understanding, however, seems to me not ideal: while in 1982 he mentioned the anomalous configuration arguments, and even put them first, he did not refer to the low-lying f orbitals there so clearly as he did in 2015, and just mentioned that thorium was a similar case. I guess the huge size of his figures showing the trends (which are properly the confirmatory argument only) did not help. So, I somewhat think that he might have gotten more traction if his article had been presented a bit more like Hamilton's... Double sharp (talk) 11:52, 10 December 2020 (UTC)

And a small funny aside
Strikes me that -Lu-Lr does better at showing what happens in group 3 in this particular way: if you show 18 columns, then La-Ac can be aligned under -Lu-Lr like I do at my table in a way that preserves the alignments that give "pseudohomologies" like Th to group 4, Pa to group 5, U to group 6. But -Lu-Lr cannot be so aligned under group 3 in an 18-column -La-Ac table. Double sharp (talk) 11:45, 8 December 2020 (UTC)

Cox @ Metal
Do you remember by any chance what that Cox, 1997 is standing for? It stays undefined since 2018. Thank you. --Nk (talk) 15:06, 11 December 2020 (UTC)
 * Same for the other sources in the same edit. --Nk (talk) 15:14, 11 December 2020 (UTC)

, I see what the problem is. The whole referencing system needs to be overhauled in that article. I've added Cox to the Further reading section, as an interim solution. Do you have an interest in metals? Sandbh (talk) 23:32, 11 December 2020 (UTC)
 * Thank you, I have found the rest of the missing references in Heavy metals - . Interest in metals - I don't have a special one, just trying to expand the article in bgwiki related to meta:List of Wikipedias by sample of articles. --Nk (talk) 08:39, 12 December 2020 (UTC)


 * Hi I was wondering if you felt in a position to support the FAC nomination of nonmetal? Obviously no obligation. Thank you. Sandbh (talk) 00:57, 16 November 2021 (UTC)

A minor but frustrating nit to pick
You recently added a section heading called "Placeholder" and then in a subsequent edit eliminated the placeholder. This meant that when I tried to follow the link in the edit summary, it took me absolutely nowhere. And with the current size of WT:ELEM, scrolling through pages and pages and pages to find the context is difficult. Not sure what the solution(s) could be, but I did want to let you know of the problem. YBG (talk) 08:18, 14 December 2020 (UTC)


 * Thanks. I'll bear that in mind, in future. I guess the same thing will happen at any time a section title is changed. Sandbh (talk) 00:42, 16 December 2020 (UTC)


 * Yea, when I add a new subsection or change the section title, I try to remember to add my own /* section title */ in the edit summary. YBG (talk) 01:43, 16 December 2020 (UTC)

PT image edit proposal
Since you created File:Taxonomic_PT_wth_halogens.jpg as a jpg, I'd suggest you make this edit to the original & upload. In the categories-legend, in the below-row add the word "metalloid" (singular). It would complete that row, instead of making metalloid(s) confusingly and inexplicitly standing out. Thx. -DePiep (talk) 18:36, 17 December 2020 (UTC)
 * Thanks DePiep, that's a good idea. Done. Sandbh (talk) 22:32, 17 December 2020 (UTC)

One more
In the same image File:Taxonomic_PT_wth_halogens.jpg, could you add the title? Top word now is "groups" ...

I'd prefer the titel to be "Periodic Table of the Elements", especially since it is our First PT for readers. Thx. -DePiep (talk) 15:11, 20 December 2020 (UTC)


 * Actually, my suggestion would be to put the title in wikitext outside the graphic. Similarly, I think it would be better to put the footnotes in wikitext outside the graphic. But this is just my idea, subject to others' thoughts. YBG (talk) 16:54, 20 December 2020 (UTC)
 * That could be done later. Situation now, it's ugly and incorrect. -DePiep (talk) 19:40, 20 December 2020 (UTC)

Done. Sandbh (talk) 21:59, 20 December 2020 (UTC)

Use of sources at WP:ELEM
Your input would be appreciated at. Thank you. YBG (talk) 21:28, 18 December 2020 (UTC)

Rearranging threads at WT:ELEM
A question and a personal request / suggestion: Thanks, EdChem (talk) 23:27, 21 December 2020 (UTC)
 * When you did the rearranging recently, was anything removed / edited, or was it only reorganisation? I am looking at a cumulative diff where so much is happening that I can't tell.
 * When doing changes like this, cutting-and-pasting in a single diff and commented as "moving X thread into Y" or whatever makes it much easier for other editors to see what you have done. Adding in one edit then removing from elsewhere in another is harder to follow, IMO, especially with multiple edits.  So, I request that you consider making moves in single edits of the entire page rather than as a series of single-section edits.
 * PS: I've just tried to make an edit at WT:ELEM.  In each case when I clicked to edit a section, the section that came up to edit was the wrong one because the thread number had changed due to your edits.  I know that your changes are making editing more difficult only inadvertently, but keeping them to a single edit would minimise this disruption as well.  EdChem (talk) 23:41, 21 December 2020 (UTC)

Nothing was removed. If I had I would’ve indicated this in my edit summaries. Entire page edits are tricky and a matter of keeping fingers crossed. Even when editing single sections I semi-regularly encounter edit conflicts due to someone else’s edits in the meantime. I will bear in mind your suggestion and seek to provide better edit summaries. Sandbh (talk)
 * Glad to hear nothing was removed... I figured that was likely to be the case, but wanted to check. :)  EdChem (talk) 11:07, 22 December 2020 (UTC)

I would go one step further: Please do not rearrange threads. It makes it very hard for those of us who try to follow this discussion by looking following the diffs. And furthermore, to move the talk contribution of other editors without their explicit permission seems to me to be at the very least inconsiderate and possibly in violation of explicit WP policies. YBG (talk) 03:35, 22 December 2020 (UTC)
 * The specific guideline is WP:TPO. It lists specific cases when it is allowed to edit others' talk page contributions. It is possible that I might have missed something, but I do not believe that the major reorganization that you attempted today falls under any of these allowed edits. YBG (talk) 03:46, 22 December 2020 (UTC)

I have semi-regularly undertaken such housekeeping in the past, with no objections. I have experienced it myself with my own edits being moved around, and that hasn’t bothered me.

A further consideration is that people occasionally complain about how hard it is to follow what’s happening on our talk page. I’ve found that too with multiple conversations on the same topic occurring in different threads in different parts of the page.

I have sometimes wondered, when looking at the TOC, how people, including me, can keep track of things.

I recall DePiep complaining about this.

The top of WP:TOP says it is best treated with common sense. I believe this is the case here. No other editor’s posts were edited by me. All original section headings were retained. The policy says, “ Never edit or move someone's comment to change its meaning…”. None of my edits, IMO, changed the meaning of the comments concerned.

In terms of following the diffs I’ll try and provide better edit summaries so that it’s clear edits of this kind these are housekeeping-relocation edits.

How does that read? Sandbh (talk) 04:33, 22 December 2020 (UTC)


 * I have been annoyed by DePiep similarly violating WP:TPO in the past, though as near as I can remember, it was never as extensive as this. My reading of WP:TPO may be wrong and it may be that your restructuring is well within acceptable WP practice. I considered asking a question about this at the teahouse or at ANI to see whether my expectations are out of line or not. But in the end, I decided to simply retire from WP for a while. YBG (talk) 04:43, 22 December 2020 (UTC)

, an informal poll may be in order. Asking at the teahouse was a good idea. Sandbh (talk) 06:45, 22 December 2020 (UTC)


 * I have reverted these, editsummary should be clear ('arbitrary' = in this case, promoting to Major/important is not clear cut to me, as there are similar threads ~equally important).
 * Grouping by topic looks helpful indeed. However, in many places there the WP:ELEMENTS editing process itself is the topic. We all should keep an eye for these interwoven threads, as they are Major by themselves. These issues should not be hidden from attention.
 * As for promoting to Major:
 * 1. I am not sure if adding 'Major' helps, given the regrouping already done. May become arbitrary. For example, from me:
 * 2. looks not needed to me, as no editing or even discussion follows from these,
 * 3., , could be considered Major (see also previous note on editing process).
 * Technically:
 * tech 1. It is good practice to leave an Anchor after section title change. It keeps existing incoming links like  functioning. So that would be:
 * tech 2. Please stop using  partitioning. It is not a common organising practice, and leaves paragraphs in doubtful state (¿what does it mean? ¿what is the status of this block?). In general, well recognised is: newline bullet=new topic in a subpost, indent=a response. A new topic may be in bold, which to me looks like a clear meaning.
 * -DePiep (talk) 09:41, 22 December 2020 (UTC)
 * -DePiep (talk) 09:41, 22 December 2020 (UTC)


 * , referring to as "similarly violating WP:TPO" is not fair, especially if you did not raise concerns with him at the time.  You can express dislike for edits or feeling uncomfortable with rearrangements without casually declaring that an editor who is not the subject of the present discussion has violated policy.  A discussion at WT:ELEM about older reorganisation as well as Sandbh's recent changes seems a sensible next step, but please leave out accusations of policy violations against DePiep or anyone else if you want a collegial discussion as comments like the one above are unhelpful.  :(  EdChem (talk) 11:20, 22 December 2020 (UTC)
 * EdChem, I stepped over that part, might have a touch of truth. Don't even mind reposting it myself. No the true problem is that YBG is retiring. please ack this clarification (so, this is not a complaint about  remarks re me). -DePiep (talk) 12:07, 22 December 2020 (UTC)
 * DePiep, I did see that YBG mentioned retiring "for a while", which I took as taking a Wikibreak rather than an actual retirement. I think it is desirable for editors to take some time away when they feel the need, but I also hope that YBG will return refreshed and re-energised. , I hope that your break is helpful and I will welcome your return when you feel able.  I hope that my comments have not detracted from your WP experience, and my comment above was more that you could have worded it to convey the same point without making what reads to me as an accusation.  For example, by saying some like that DePiep has made similar reorganisations which have led to you uncomfortable given WP:TPO and that Sandbh's more extensive changes are even more concerning.  The ELEM team has had far too much tension and friction and so I am encouraging everyone to try to choose words so as not to trigger tensions as everyone may still be over sensitive.  , does that address your concern?  I am not certain how to interpret your request that I "please ack [sic] this clarification."  Please note that I posted the above comment before seeing that YBG had archived his user talk page, etc, which I agree does look more like retirement than a simple Wikibreak. EdChem (talk) 20:57, 22 December 2020 (UTC)
 * My point was in the "retire for a while" part, not YBG's comment about TPO. (So, I responded to point to this, after your 12:07 post here replying to the earlier part, eg "not fair", to prevent the talk going in an unintended direction). An editor "retiring", even it temporally, is a bad signal for the ELEM project. It signals frustration with the goings, while YBG repeatedly tried to get WT:ELEM back on track, carefully, over a very long period including recent weeks. Some days before, another editor expressed anger and wanting to walk away from the talks. And some editors have not yet returned to cooperating in the stormy content issues. In other words, the intentions expressed when ArbCom came in sight look like showing cracks. Is what I call problematic. -DePiep (talk) 21:29, 22 December 2020 (UTC)

YBG has retired for a short break on at least one other occasion. I expect he will be back, at a time of his choosing. Sandbh (talk) 04:53, 23 December 2020 (UTC)

PT edits
Why not create explicit consensus first? -DePiep (talk) 01:34, 26 December 2020 (UTC)


 * , consensus is not required before editing.


 * Re Double sharp, he said, "So, you can do what you want, and I'll let people who actually are going to be active comment on it if they so wish."


 * I extended Double sharp the courtesy of notifying him of my intention to revert. I did not do so until he posted the above.


 * I am now attempting to contribute to the effort to bring the periodic table article back up to FA status.


 * As a fellow member of WP:ELEM may I please have the courtesy of some revert-free space so that I can continue my work? If you subsequently have any concerns could you please first discuss them at WP:ELEM, before reverting?


 * If I do not hear from you shortly, I'll continue my work, and IGF undo your revert. I hope this will be OK.


 * thank you, --- Sandbh (talk) 01:51, 26 December 2020 (UTC)


 * re: consensus is not required before editing Sure, except for editwarring of course. Anyway, Your edit is the "B", I did "R" (no consensus need either, we know), so we are at D now. (No need to threat "If I do not hear from you shortly"; it's not BR D T. Proceeding after this may be considered editwarring).


 * I note that in this editsummary you mentioned "per WT:ELEM" without a link. So you did claim consensus. However, I cold not find it, and nor did you link to it in the es nor in your answer here. (you only suggest consensus by interpretation of isolated quotes). Why not ask for explicit agreement, beforehand? -DePiep (talk)


 * , thanks for the quick response. Could we please not get bogged down here? I'd be grateful for that. As a fellow member of WP:ELEM could you please extend me the courtesy of some revert-free space, following DS' advice, as I posted above, that "…you can do what you want, and I'll let people who actually are going to be active comment on it if they so wish."? Please note DS's reference to commenting on edits (rather than reverting).


 * For the record:


 * In your reversion, you included my reversion of DS' edits. You are in breach of BRD.
 * Given DS's post, this has nothing to with edit warring.
 * My reference to not hearing from you shortly wasn't intended as a threat, sorry. I was looking forward to some further editing for the rest of this afternoon and didn't want to be left hanging, not knowing how long you'd still be online.
 * The reference in my edit summary to "per WT:ELEM" was a reference to DS' comment.
 * Given what he said, there is no need to now ask DS beforehand.


 * Could you please let me know if you would extend me the courtesy of some revert free space? If I do not hear from shortly, I intend to continue editing. This is not a threat. I'm trying to make best use of my time, that's all.

Thanks again --- Sandbh (talk) 02:46, 26 December 2020 (UTC)


 * Yes in a 16k revert some comma might be reverted unintentionally. Up to you to establish consistent editing, not me.


 * TL;DR. -DePiep (talk) 02:49, 26 December 2020 (UTC)


 * Could you please let me know if you would extend me the courtesy of some revert free space? If I do not hear from shortly, I intend to continue editing. This is not a threat. I'm trying to make best use of my time, that's all. Sandbh (talk) 03:43, 26 December 2020 (UTC)


 * If I do not hear from shortly, I intend to continue editing. This brutality.


 * To be clear: No, I do not give you any leeway re editing and reverting. That is because you do not edit from talk & consensus. And this is not about fixing typo's, it's about deleting -8k, -16k. The only arguments I hear from you are, like, 'bold does not require talk'. Not once, in recent times, did you engage in a communal talk to get some agreement. Your WT:ELEMENTS contributions, as I haved noted there before, are only describing you taking freedom to edit-without-discussion; invoking policies that fit you, but not self-reflecting on policies that might be, eh, mitigating your edits.


 * Now you could go on editing this way without my "approval". I just want to note that, with this beaviour, you are putting our WP:ELEMENTS group at risk. That is: think ArbCom. It might not have to do with me or my edits at all. -DePiep (talk) 04:03, 26 December 2020 (UTC)


 * , Thank you. May I continue editing without your approval and being reverted by you, until I complete my current round of edits? You may take me to WP:ANI or Arbcom in the meantime, if you like. I will notify WP:ELEM when I have shortly concluded.


 * The 1st deletion you mention is ancient history, being done on 15 Nov, as part of the fresh energy initiative for improving the PT article. The 2nd deletion you refer to is not a deletion but a reversion by me, as I flagged at WP:ELEM for discussion and did not do until Double Sharp posted his statement that I could do as I wanted, subject to other people commenting. Since you reverted my reversion, you are in breach of BRD.


 * Bear in mind the recent edits by Double sharp were not discussed before hand. He posted his comments after the edits. The same thing happened with the other recent edits to the periodic table. I am asking for the same approach to be extended to me.


 * Bear in mind I discussed some items to consider in going forward with the PT article, here. The only person who commented was Double sharp. Since he has now withdrawn from the discussion, I am proceeding in accordance with those items.


 * Thanks again for your prompt responses. Sandbh (talk) 04:28, 26 December 2020 (UTC)
 * Sandbh, YBG is taking a break.  is stepping back and my reading of his comments is that he was expressing frustration at the editing environment.  His withdrawal did not read to me to be an endorsement that you should go ahead with what you think is best; I read it as giving up having lost the will to continue discussing.   is expressing frustration even more clearly, in my opinion.  A request for revert-free editing as the best use of your time when you have posted an intention to revert others certainly strikes me as seeing your contributions as worth more than those of others – though I can't speak for either of them, of course.  Your recent edits to WT:ELEM include more advocating for La over Lu in group 3, despite supporting the thread that decided to leave the topic until IUPAC says something.  They also include more material on B-Al in group 3 rather than 13, which is a historical fact that is used in no modern PTs and which you continue to be pushing.  Editors leaving a project is never a good sign.  My observations and the comments I have read lead me to suspect that you are a significant factor in both YBG's and Double sharp's choices.  These are not good developments, in my opinion.  EdChem (talk) 06:31, 26 December 2020 (UTC)


 * Thank you, EdChem.


 * YBG has temporarily left the project in the past. He'll be back. Double sharp has left the project in the past. He continued to contribute. He returned to the project. He has now left the project. Based on previous experience, he'll continue to contribute, and he'll return to the project. Project membership counts; contributions count more.


 * As Double sharp said to me:


 * ""So, you can do what you want, and I'll let people who actually are going to be active comment on it if they so wish."


 * How does that read to you?


 * Yes, I posted an intention to revert some edits by Double sharp (not those of "others"), out of courtesy, so that discussion could ensue, which it did.


 * Only when Double sharp posted what he did, and he was the only one to discuss the dozen suggested items to consider in going ahead, did I revert. In contrast, there were no contributions or discussion before DePiep reverted, including a breach of BRD.


 * Yes, I posted some content about the group 3 issue in the interesting publication section, not to revisit that in the context of the periodic table article, but to share information, including in the context of the IUPAC project, which at least Double sharp and I are looking forward to reading. As the hat note at the top of the interesting publications section says, "When a publication gains traction and responses, please start a separate thread." I was not expecting any responses.


 * I would be pleased to learn of any evidence of me continuing to "push" B-Al over Sc in the article space. In the isodiagonality PT in the periodic table article, before I was reverted by DePiep, I showed Al in two places, over Sc (shaded), and in its ordinary place in group 13. I added a contextual explanation of what is going on, in the notes under the periodic table. I relocated a part of these notes, into a footnote proper. I made each of adjustments taking on board Double sharp's concerns; I'm not doing what I "think is best", as you say. I edit in the context of discussion and concerns raised at WP:ELEM. There is no B-Al in group 3. The only place there should be mention of B-Al over Sc is in the historical section.


 * I was going to continue editing the periodic table article IGF and in the context of discussions at WP:ELEM. I'm not inclined to do so in the face of the potential for capricious reverting.
 * --- Sandbh (talk) 07:28, 26 December 2020 (UTC)

Consensus Requests
Hi Sandbh,

I note your recent restructure of the consensus requests at WT:ELEM, which I think was a good change. I am wondering if you would mind a further separation of proposals from discussion. I don't mind doing it (or you can, if you prefer) but I think having (a) the proposal and (b) discussion of it (including your rationale) would be easier to follow, or even (a) proposal, (b) rationale, and (c) discussion.

Thanks, EdChem (talk) 21:47, 29 December 2020 (UTC)


 * Thanks; please go ahead as you see fit. Sandbh (talk) 00:19, 30 December 2020 (UTC)

Community-imposed topic ban
In this discussion, specifically here the community decided to impose a six-month topic ban on you from the topic of chemical elements, broadly construed. This means that you are not allowed to edit any page related to this topic until six months after this message, or you may be blocked from editing; see WP:TBAN for more details.  Sandstein  20:32, 3 January 2021 (UTC)

Triggering
Hi Sandbh,

I want to acknowledge your ANI post in which you disclosed your battle with major depression, your experiences of triggering, and having had thoughts of self harm at times. I feel great empathy for your suffering as I too have those experiences. In fact, I am presently struggling with my most difficult period of the year, from a little before Christmas until towards the middle of January, where I have a series of anniversaries of traumatic events that make me vulnerable at this time and likely to experience unintended triggering events. I reached out to DePiep regarding his post as I know how awful these experiences are for me, and I hate the idea of triggering others even accidentally. I also reached out as I know that acceptance and understanding can be helpful.

Sandbh, I am very sad to hear that you too have major depression and face the difficulties that can come with it. I want to thank you for the trust involved in making the disclosure, and to say that it has helped me to understand better how you have responded at times. I also want to apologise for any triggering or distress that I have caused or added to in this time. I hope that I have done more good than harm, as I hope is true of all my contributions. My own issues lead me to be harshly judgemental of myself at times and to struggle to be objective in self-assessment and reflection, which is a challenge that I continue to face. I also hope that you can accept that the comments that I have made about you and regarding you were made honestly and are not intended to be hurtful / harmful.

, though this is not your page, there is somthing that I think it appropriate that I acknowledge to both you and Sandbh. When I am struggling with depression, one of my responses is to try to be extra-helpful / useful for others. I won't call it a coping mechanism as I am not sure that it is necessarily always helpful. I am wondering about how this tendency has fed into my suggestion for a page in my user space. DePiep, I truly did not intend it as a back door for Sandbh to side-step the tban, but I can see how it could have facilitated that inadvertently. I can also see how it could be triggering for you, given the immediate post-ArbCom events. It appears that we have all had experiences that are leading to actions with inadvertent consequences. Sandbh's participation in the topic area has importance to him that makes a tban a potential trigger – so leading to efforts to find any alternative. Those efforts, viewed through a typical ANI lens, made the tban inevitable – in effect, seeking to avoid a trigger led to the triggering becoming unavoidable. My need to be helpful led me to try to find a form of on-wiki inclusion that prevented ongoing problems and disruption, which had a form that was triggering to DePiep and led to disagreement about the idea... and as a consequence, I am feeling like I have failed to be helpful in the way that I was trying. I am also feeling annoyed that the close did not address the scope of the tban, as requested, which led Sandbh to post a request for clarification that could be used against him.

Sandbh, in any response you make, please avoid talking about the area of the topic ban in any way – there are some who take any alleged "boundary testing" very seriously, and you do not need or deserve any more attention than is already occurring. I posted here as I think there is value in recognising the mental health issues that have been connected with recent events. Hopefully, that will lead to better understanding of each other.

Kind Regards,

EdChem (talk) 00:17, 5 January 2021 (UTC)


 * Dear


 * I appreciate your post, and the thought that went into it. I'm sorry to hear this time of the year can be tough for you. Are you able to get past such events, rather than dwelling on them, or forgetting them? I like to think we are not defined by our past, unless we choose to be for whatever reason. I try to look forward.


 * On the comments you made about me it's good to know these were made in honesty. I try to do the same.


 * I'm puzzled as to the purpose behind making a topic ban so vague. What's so hard about a black and white ban? Beats me.


 * I've heard from DePiep, Droog Andrey, ComplexRational via PM and will keep in touch with them. Nothing yet from R8R or Double sharp.


 * I have a few WP articles or essays that I can work on, as listed at my talk page, and some other projects.


 * Best regards, René aka Sandbh (talk) 07:10, 6 January 2021 (UTC)

Strikethrough
Please use  – or the (a.k.a., ) template wrapper for it. The  version has not been valid HTML since the 1990s. Use of obsolete tags impedes our migration to HTML 5 and creates extra cleanup work to do. If you would like to help with tag cleanup, please see WP:LINT and WP:HTML5. — SMcCandlish ☏ ¢ 😼  03:40, 7 January 2021 (UTC)

Freezing of mercury
Hi, I do not get the first sentence in the discovery of nonmetals, sorry. The fact is missing which connects the freezing of mercury with the discoveries, or is it a simple time stamp, like the "after George Washington got married" (the same year).

Nice to see that the Element pages are still on the way, even without me and a lot of the others which did the job 10 years ago. Have fun! --Stone (talk) 14:59, 8 July 2021 (UTC)


 * Dear Stone, I was pleasantly surprised to hear from you and to learn you are still around. Coincidentally, my first wp edit was ten years ago, in June 2011. It'd be fair to say it has taken me that long to become sufficiently familiar with the subject matter of nonmetals. The reference to the freezing of Hg was a time stamp. I've now made this clearer in the article. There is some more work to be done on the article to bring it up to FAC level; it has been fun so far. Thank you, Sandbh (talk) 01:05, 9 July 2021 (UTC)
 * I look every now and then, but I work and family leaves only minimal time. -Stone (talk)

costs of elements
In case you haven't seen that list already: Prices of chemical elements might be useful. :) Double sharp (talk) 13:37, 9 July 2021 (UTC)
 * Thank you. I stumbled upon that one a couple of days ago; I didn't know it existed. Sandbh (talk) 07:58, 10 July 2021 (UTC)

A not very serious question
If we were living on Pluto, I wonder if you'd consider Sn a metalloid or nonmetal. After all, then alpha-Sn would be considered the standard state. :) Double sharp (talk) 14:40, 3 September 2021 (UTC)


 * Grey tin as a metalloid, or even a nonmetal, has a few things going against it.
 * Tin has no semiconducting allotropes, unlike the elements commonly recognised as metalloids (ECRAM). Seeger (1991 p. 30) says that grey tin, although actually being a semimetal, in electrical measurements acts like a semiconductor having a gap of 0.09 eV.
 * Sanderson (1960, p. 82) observed a quite abrupt transition from lower heats of fusion in metals, after whose melting much of the stronger bonding still persists, to higher HoF in metalloids, which have more specific structure that breaks down completely on melting: Be (11) to B (22); Al (10) to Si (50); Ga (5.6) to Ge (31); Sn (7) to Sb (19.8). This can be seen to in Pb (4.7) to Bi (11) but other considerations come into play for Bi. I presume the HoF for grey tin would be in the same vicinity as white tin; this source gives an experimental mp for grey Sn as 220±13 °C cf. white Sn 231 °C. So, physically, grey Sn does not appear to match the metal to metalloid pattern.
 * Unlike the ECRAM, tin forms a relatively well-characterised hydrated +2 cation in aqueous solution (Richens 1997, p. 152).
 * Smith (1973, p. 558) says Bi is a typical "B" metal like Sn or Pb (i.e. physically and chemically weak).
 * Moody (1969, p. 267) writes that hot concentrated sulphuric acid yields the dioxide when acting on the non-metallic elements, being reduced to SO2. However Sn is sufficiently metallic to form a mixture of SnO2 and sulphate, while Pb forms PbSO4.
 * Tin can form many more alloys with metals, than is the case for metalloids.
 * Tin can form Zintl phases, which is something that AFIAK, only applies to post-transition metals or metalloids, rather than extending to nonmetals.


 * Probably #3 and #6 are killers.


 * Here on Earth, Cohen and Chelikowsky (1988, p. 99) regard grey tin as a very poor metal, which is a rather good description; Pauling (1988, p. 577) said it has the properties of a metalloid (I guess he was referring only to some of its physical properties, e.g. it being brittle; having the diamond structure; sub-metallic electrical conductivity; and seeming to Pauling to be a semiconductor); and Ebbing and Gammon (2010, p. 891), who distinguish between metals, metalloids, and nonmetals, treat grey tin as a nonmetal and describe it as a brittle grey powder, suggesting they didn't do their homework.


 * Perhaps, whether on Pluto or Earth, there'd be more gained by referring to grey tin as a near metalloid (on the left side of the notional dividing line between metals and nonmetals.


 * References
 * Cohen ML & Chelikowsky JR 1988, ''Electronic Structure and Optical Properties of Semiconductors, Springer Verlag, Berlin
 * Ebbing DD & Gammon SD 2010, General Chemistry, 9th ed., Brooks/Cole, Belmont, CA
 * Moody B, Comparative inorganic chemistry, 3rd ed., Edward Arnold, London
 * Pauling L 1988, General Chemistry, Dover Publications, New York
 * Richens DT 1997, The chemistry of aqua ions, John Wiley & Sons, Chichester
 * Sanderson RT 1960, Chemical periodicity, Reinhold, New York
 * Seeger K 1991, Semiconductor physics: An introduction, 5th ed., Springer-Verlag, Berlin
 * Smith JD in Bailar et al., Comprehensive inorganic chemistry, Pergamon, Oxford

-- Sandbh (talk) 07:45, 4 September 2021 (UTC)
 * Thanks for your thoughts! I did say it wasn't a serious question, so it's a pleasant surprise to get a well-researched reply. So, perhaps Plutonians would treat tin the way we treat bismuth: by band structure not a true metal, but chemically persuasive enough. :)
 * You got me curious about HoF values. I think this is another of those things that only holds good for main-group elements. The transition metals often have incredibly high values, e.g. rhenium 60.43 kJ/mol! I guess this must be the covalent contribution to the bonding helping. Also, it's interesting that polonium is higher than bismuth (though I wonder how well it was actually measured). (Relativity is apparently responsible for why Po does not follow the structure of Se and Te.)
 * What would you include in "near metalloids"? Among PTMs, I guess the term makes some sense for Al, Ga, Sn, Pb, Bi, Po. But In and Tl might be too far. Double sharp (talk) 08:43, 4 September 2021 (UTC)
 * Probably C, P, Se, α-Sn, I, Bi. I wrote about this,, as follows:


 * "An interesting and elegant solution for accommodating these metalloid-like elements was provided by Adler47 who suggested defining a metalloid simply as a semiconductor or a semimetal. His suggestion can be viewed as a step too far; few other authors have regarded these additional elements as metalloids. As well, the question of which elements would be counted as insulators rather than semiconductors was not addressed.
 * There may be some merit in adapting Adler’s suggestion by distinguishing between the notion of a “metalloid”, and that of a “near metalloid”. Metalloids are those elements commonly recognized as such, which fall within the scope of the definition set out in this article. A near metalloid then becomes any other chemical element having the electronic band structure of a semimetal or a semiconductor, with the latter (for this purpose) being taken as an element having a band gap less than or equal to the visible spectrum cutoff of 1.8 eV.48 A semiconductor with such a relatively narrow band gap49 has a metallic or black appearance,50,51 and metalloids have traditionally been regarded as looking like metals52 (semiconductors with wider band gaps, and insulators, appear colored, white, or transparent).53,54 This definition would include graphitic carbon, black phosphorus, gray selenium, gray tin, iodine,55 and bismuth. As noted, these are all elements described in the literature as being metalloid like, or words to that effect. Craig,56 for example, refers to the “near metalloidal” status of selenium; Schroers57 refers to carbon and phosphorus as near metalloids. Although aluminum and polonium are also mentioned in the literature as showing some metalloid character, both elements have the electronic band structures of metals and, arguably, show at least a reasonable preponderance of metallic character. They are both better regarded as poor metals or chemically weak metals.37,38"
 * It's cute that there are six elements commonly recognised as metalloids, and six near metalloids (in this scheme).
 * Sandbh (talk) 00:43, 7 September 2021 (UTC)
 * Ah, so you are including the nonmetallic side too! That certainly makes more sense than including just some p-block metals.

Perhaps hydrogen needs some kind of word, too, for its chemistry rather than its physics. Double sharp (talk) 15:00, 9 September 2021 (UTC)
 * Perhaps a quasi-metal? Sandbh (talk) 23:47, 9 September 2021 (UTC)
 * Nice! Double sharp (talk) 07:12, 10 September 2021 (UTC)
 * "Hydrogen as a quasimetal, a concept introduced by Graham, is still a fruitful working hypothesis." Here:, p. 2 according to Dr G. :) Sandbh (talk) 02:08, 14 September 2021 (UTC)

Just a thought ...
In the nonmetal article, I think it would be better if you treated the classes in the reverse order from what you are currently doing. To me it makes better sense to start with two classes that are well defined and clearly classified as nonmetals, then the less-well-defined class that are still clearly classified as nonmetals, then for comparison, the class that is not-so-clearly nonmetals; you could even go on to compare the metals themselves. Just a thought. YBG (talk) 08:50, 5 September 2021 (UTC)
 * Not this L-to-R order: (1) metalloids (2) unclassified nonmetals (3) halogen nonmetals (4) noble gases
 * But this R-to-L order: (1) noble gases (2) halogen nonmetals (3) unclassified nonmetals (4) metalloids
 * I think this thought makes a lot of sense too, especially since the noble gases and halogens are quite a lot better as "stereotypical nonmetals" than metalloids (which aren't always included) or unclassified nonmetals (because of things like selenium). Double sharp (talk) 08:46, 6 September 2021 (UTC)


 * I tend to agree. The order I’ll try (not quite the same as that suggested) is: nonmetal halogens; unclassified nonmetals; metalloids; noble gases. I get the sense of NG; halogens; UC; and metalloids, and that the NG and halogens are well defined. OTOH the NG are not typical examples of nonmetals given they (uniquely) don’t bond with one another; their lack of anionic character ; and that they bridge the halogens and the alkali metals. Whereas the nonmetal halogens are well defined, and exemplars of nonmetallic behaviour. Now, the elements commonly recognised as metalloids, for authors who distinguish metalloids, are separated from the nonmetal halogens by a potpourri of UNC nonmetals, so I feel it makes sense to list them (the UNCs) next. Sandbh (talk)
 * Other advantages of the original scheme include:
 * it is PT order, albeit R-to-L, and so it keeps the reader who is consulting a periodic table from experiencing whiplash.
 * the two categories (group 17 & 18) which are both well-defined and universally considered NM are listed before any categories less-well-defined or not-universally accepted as NM
 * the three categories universally accepted as NM are listed before any categories that are not universally accepted as NM
 * the category not universally accepted as NM (metalloids) is listed last, so that it can reasonably be introduced by saying "for comparison, the metalloids, which are sometimes considered to be nonmetals, are ..."
 * it can easily be expanded to include the metals after the metalloids, again by stating they are mentioned "for comparison, the metals are ..."
 * YBG (talk) 00:09, 7 September 2021 (UTC)
 * Done! Looks good, too. Thanks YBG. Sandbh (talk) 00:57, 7 September 2021 (UTC)

Regarding metallic astatine
Something mighty interesting in this historical review that I haven't yet followed up: Since elements at heavier periods often resemble their n+1 and n-1 neighbors more than their lighter congeners, eka-iodine also was expected to be radioactive and metallic like polonium. So apparently the early workers probably had the right idea all along! Double sharp (talk) 14:06, 13 September 2021 (UTC)
 * An excellent find, thank you! The line about n+1 and n-1 neighbors is pricless. I've added it to the At footnote in the Definition and applicable elements section. Sandbh (talk) 01:59, 14 September 2021 (UTC)

You probably won't believe me
But I'd forgotten about that barn star. In any case there was no COI. Doug Weller talk 17:39, 27 September 2021 (UTC)


 * G'day again. I'd forgotten all about that. So much water under the bridge. I believe you. That wasn't the issue. It was the perception of a COI, that was the concern. Food for thought perhaps. Sandbh (talk) 06:58, 23 October 2021 (UTC)

What is your preference?
I know your ideas about chartjunk, and so I'm asking your opinion about these options Thanks! YBG (talk) 00:46, 9 October 2021 (UTC)
 * 1) special:permalink/1048955755
 * 2) special:permalink/1048955584
 * 3) special:permalink/1048840421
 * 4) special:permalink/1046688776
 * PS, I wanted to transclude them, but, alas, I could not. I even went to Villiage Pump to ask. Fortunately, I checked the archives before posting the question. The question had already been answered back in 2015 at . Good thing I didn't ask, it would have been really embarasing. YBG (talk) 00:52, 9 October 2021 (UTC)

Nonmetal
Hiya! I saw your effort to make nonmetal an FA. We don't see enough vital articles at FAC, so I'm really happy to see this. I'm a bit busy now with the climate change TFA preparation, and my sustainable energy FAC, but might have some time to give feedback before the next round at FAC early November. From a quick glance, I'd say the article could benefit from a copyedit (not really my expertise) and a idiot lay person review (I didn't do much chemistry after secondary school, so should be able to help here). Thanks for your work! Femke (talk) 08:43, 21 October 2021 (UTC)


 * Nice to meet you on my talk page, and thanks for the kind words. The reference to the article as being vital prompted me to actually look this up on wp. So I know now what the significance of a vital article is. FAC #3, all going well, will be 1 Nov. I intend to copy edit the article by reading it from the end to the start, rather than the start to the end which I've done way too many times to now be able to copyedit it that way. If you have the interest and time for a layperson-read that would be most welcome. I'll see if I can get round to reading your sustainable energy FAC. Sandbh (talk) 06:52, 23 October 2021 (UTC)


 * The sustaible energy FAC should be nearing its end now. I'll see if I can make some time tomorrow for some feedback :). Femke (talk) 07:03, 23 October 2021 (UTC)


 * Hi I was wondering if you felt in a position to support the nomination? Obviously no obligation. Thank you. Sandbh (talk) 00:55, 16 November 2021 (UTC)


 * Reviewing the entire article is unfortunately still out of reach for me. I'm recovering from long covid and reading something from a different field drains too much energy. I see a lot of my talk page comments have been addressed :), but there are some remaining. Femke (talk) 17:08, 16 November 2021 (UTC)

Inconsistencies and the "culture" at FAC
Happy to discuss my experiences over the last decade or more, in private if necessary, as obviously such discussions aren't welcome in some quarters of Wikipedia...! The Rambling Man (Keep wearing the mask...) 18:13, 27 October 2021 (UTC)

In appreciation
Thank you very much (!) That was an unexpected, pleasant surprise ^_^ Civility is evidently a fine thing! Sandbh (talk) 07:27, 13 November 2021 (UTC)
 * I concur with Gog's assessment and appreciation. YBG (talk) 10:01, 13 November 2021 (UTC)

Nonmetal structures
Roughly speaking, I suppose one could distinguish between dimensionality of the structure of covalent bonds more or less as follows:


 * 3D: C (diamond), Si, Ge, Sb (grey)
 * 2D: C (graphite), P (red, black), As (grey, black), Sb (black)
 * 1D: Se (grey), Te
 * 0D (molecular): H, He, N, O, F, Ne, P (white), S (yellow), Cl, Ar, As (yellow), Se (red, black), Br, Kr, I, Xe, Rn

I count, say, black P as 2D because the covalent bonds do not extend indefinitely in all 3 directions. Grey arsenic is a bit of a close call, but there's noticeable difference between how much delocalisation you get in each direction. For antimony it is closer, might as well be considered 3D already. YMMV on where to draw the line: if we just look at structures, not too much difference between grey Sb and Bi. (But hey, it's just one of many criteria to help triangulate.)

Incidentally, sudden shift from 1D chain structures of Se and Te to 3D structure of Po thanks to 6p3/2 destabilisation does make me more willing to believe in fcc At than before. Double sharp (talk) 14:46, 20 November 2021 (UTC)

Talk page refactoring
Moving comments around is generally frowned upon, but if you decide to do so, please do it in a single edit rather than cutting in one edit and pasting in the second edit. This is slightly more difficult for you because you have to edit the page instead of editing sections, but it means that anyone who looks at the edit in the future can immediately see that the paragraphs were moved without change. The WP software conveniently uses arrows to show paragraphs that are moved with no change or with very few changes. Thank you. YBG (talk) 04:06, 21 November 2021 (UTC)


 * YBG, There is no indication from WP:REFACTOR that moving comments around is generally frowned upon, and it assumes good faith which in this case there surely was. If further advises, "Good refactoring practices are an important part of maintaining a productive talk page." I'll bear in mind your preference but don't expect it if I'm working on an iPad or a phone. Sandbh (talk) 04:21, 21 November 2021 (UTC)

May I have your permission ...
... to reformat your entry at so that it is a single bullet? YBG (talk) 06:11, 21 January 2022 (UTC)
 * Yes indeedy. Sandbh (talk) 06:28, 21 January 2022 (UTC)

TPO for starters
I am surprised that I have to tell you, once more, on how to behave in a discussion. This edit is unacceptable. That includes the misleading editsummary. You'll understand this is tearing my patience (with you & your editing behaviour). There are other paths to walk if you have questions or issues (but not me is gonna point them out to you any more). I will not accept you breaking or spoiling a discussion. So best consider this as a serious warning. -DePiep (talk) 08:14, 22 January 2022 (UTC)

I appreciate your remarks
Thank you! Buffs (talk) 14:53, 24 January 2022 (UTC)

Good article reassessment
Nonmetal has been nominated for an individual good article reassessment. If you are interested in the discussion, please participate by adding your comments to the reassessment page. If concerns are not addressed during the review period, the good article status may be removed from the article. CactiStaccingCrane (talk) 16:18, 9 February 2022 (UTC)

No thanks
There is no need or use to thank for each and every edit. Unless you want to signal something -- which then better be 'signaled' directly. Even worse, it might be experienced as owning or parenting. -DePiep (talk) 08:33, 25 June 2022 (UTC)


 * Given our chequered history as members of WP:ELEM my thanks for your edit, however minor, was intended to express my appreciation of your contribution. In future I'll bear in mind your view on such things. Sandbh (talk) 00:12, 26 June 2022 (UTC)
 * Fair enough, and that is how I read it erlier on. Now fixing a typo is hardly noteworthy. Edits, even minor doubtful edits, otoh, can be dicussed etc. as ever, or a careful rv-es could do. -DePiep (talk) 06:05, 26 June 2022 (UTC)

New message from Jo-Jo Eumerus
Jo-Jo Eumerus (talk) 14:08, 1 November 2022 (UTC)

Email
Hi Sandbh. I received your email but you may not be aware that the system does not include your reply address unless you deliberately put it in the text. I am happy to chat about the Group 3 problem but my ability to contribute will simply be to evaluate sources: as an organic chemist by (ex) profession I have no personal expertise on the subject. This is normally better done on-Wiki on Talk Pages so all interested editors can engage. I have used email, for example recently to supply Double sharp with some .pdf of sources but that's only because for copyright reasons such material has to go via email attachments. Mike Turnbull (talk) 11:52, 10 November 2022 (UTC)

Exchange of views (Eov) 1
Since you just referred to it at Talk:Periodic table, I feel I should explain this.

The essential case of the 2017 submission appears to have been as follows (at the very least, that's what felt the most important to me): If that was all true and uncontroversial, I'd support Sc-Y-La still. However, since the submission, and after some conversations with DA and others, I found various considerations that make these arguments weaker: Given that, I think it is not surprising that I changed my allegiance. The thing that tipped it over for me is: if La and Ac have valence f involvement, but Lu and Lr don't, then why call Lu and Lr f-elements? If Ac and Th both have chemical 5f involvement, and neither has 5f electrons as a ground-state gas-phase atom, then shouldn't they be treated in the same way? And if the rare earths are so close in chemical properties, then why split the blocks at all? It would presumably put the (much more different) 2p elements' placements in jeopardy.
 * 1) If group 3 is treated as transition, then it makes more sense as Sc-Y-Lu, to match groups 4-8. If it is treated as a main group, then it makes more sense as Sc-Y-La, to match groups 1-2. (Per "1965: Similarity of Lu with Sc and Y"). But the behaviour of group 3 is more like that of a main group than a transition group (per "Chemical behaviour").
 * 2) Weak f-character seems plausible for La and Lu, but Lu at the end of the f-block better matches Zn at the end of the d-block, as neither shows involvement of the characteristic subshell. As we wrote under "Blocks", Now, if we were to start the f block at La and end it at Yb, it would start before the f orbitals are capable of becoming chemically active and stop just before they sink completely into the core. It is worth considering the Sc–Zn case similarly. At the end of the block we have Cu, [Ar]3d104s1, with a filled 3d shell that can still be ionised. The next element is Zn, [Ar]3d104s2, with a 4s differentiating electron; but the d block effectively ends here because this is where the d shell first becomes chemically inactive. Is this not more similar to Yb (in an -La-Ac table) and Lu than to Tm and Yb (in an -Lu-Lr table)?
 * 3) Th is not a direct comparison because it shows 5f involvement.
 * 4) Condensed-phase configurations have fewer irregularities in a Sc-Y-La table.
 * 5) La-Ac are a pair out of place.
 * 1) The behaviour of group 12 is also more like that of a main group than a transition group. But that seems to suggest that Be and Mg should be in group 12. So the argument doesn't seem that conclusive after all. Also, consider Zr, Hf, and Rf in group 4. They do not show very much complex coordination chemistry because there's too few d-electrons for pi backbonding (the end of the G&E chapter on group 4), they don't show multiple oxidation states, they're very electropositive and reactive (just forming an oxide layer like Al). In that way they look also like valence-4 s-block, main-group metals. So group 4 is split between one transition-ish element (Ti, which even then prefers +4) and three main-group-ish elements. Main-group behaviour is actually the majority. Maybe it makes sense to split Sc from Ti, but by this logic, does it really make sense to split Y from Zr? Or La/Lu from Hf?
 * 2) Zn is not a match after all. 3d is actually bonding (Tossell 1977) in ZnF2. However, nobody could confirm such a thing for Lu. So the parallel Zn-Lu is weak. Tossell 1977 in fact parallels an interesting Chinese paper, as Tossell notes that you need highly electronegative ligands to coax the 3d of Zn out. Well, the same is true for 4f in Yb, per that Chinese paper; you need something like F or O. But 4f can't be coaxed out for Lu even by F and O. That rather suggests a Zn-Yb parallel.
 * 3) Wittig, Gschneidner and others have been suggesting that 4f may be responsible for some properties of La. They are made quite plausible by the fact that those anomalies are never seen anywhere outside the f-elements. Even in 2017 we wrote we found evidence for the former effects to be plausible about Gschneidner on thermodynamic properties. Just as an example that Wittig points out, dhcp is never seen outside the f-elements, for example. Yeah, it's true that La is larger than Sc and Y, but look at the alkali metals. Li and Cs are so different in size, but they are both bcc. So obviously size differences are not enough of an explanation. Something else must be going on. And indeed, in the alkaline earth metals something else is going on (in Ca 3d appears), and there is a change between Mg hcp and Ca fcc. This strongly suggests that Th is in fact a direct comparison with La, contrary to what we thought: Jørgensen says that the level of f-involvement is similar for both. In particular, I am not aware of any other explanation that has been invoked to explain why La's melting point is lower than expected, except for 4f involvement per Gschneidner. I attach a graph from his last paper where he shows the value calculated for La's melting point if there weren't any 4f hybridisation. I have no answer to that whopping 450 K difference. There is chemical evidence for dative 4f-2p bonding in LaF3 and some 5f-occupancy in Ac(HOPO). But then we're back to Jensen's point that it's inconsistent to allow Th in the f-block but bar La and Ac. Even though I agree that some other parts of his case are not that solid (they would suggest Be-Mg-Zn, as Ca is usually different from those three), I find his point strong here: surely we can't change the rules between two elements that are exactly next to each other (Ac and Th).
 * 4) Condensed-phase configurations support Be and Mg over Zn, per your table. This was not addressed in our case. Since the position of Be and Mg over Ca is extremely well-settled at this point this weakens the argument.
 * 5) Since 4f involvement for Lu could not later be substantiated, Lu-Lr equally become a pair out of place in the Sc-Y-La-Ac form. In fact, they're even worse than La-Ac in the Sc-Y-Lu-Lr form, since at least La and Ac have some kind of valence f-involvement low enough to make some kind of physical (and perhaps chemical) difference. Where's that for Lu and Lr? Wittig and Gschneidner don't think there is any for Lu, at least.

Finally, the d-involvement in Ca-Sr-Ba isn't an exact parallel. Sc, Y, La, and Lu all have 3 valence electrons, so something else has to decide. But per Tossell, Zn has 12 valence electrons (3d+4s), whereas Be, Mg, and Ca obviously only have 2. So there's a reason to have Be-Mg-Ca that doesn't have a parallel for Sc-Y-La.

P.S. Re Jørgensen, he says that the 4f element ions Pr3+ through Yb3+ show characteristic narrow bands with their positions almost completely independent on the ligands, but the following 5d elements (along with the 3d and 4d elements) behave significantly differently; while both types of elements show electron-transfer bands, ligand field theory becomes important for the d elements. I presume this is his reason for saying Lu is more conveniently considered as 5d.

P.P.S. Wulfsberg makes perfect sense if he's referring to the +2 cations rather than the +3. Not only is that more realistic for formal LnIII cations in terms of real charge, it also makes sense of why he refers to both the f-block and the d-block elements in the same paragraph. Then there is no standard oxidation state across the d-elements that is universally stable. But +2 makes some sense for all of them as a baseline that ionises the outer s2 electrons. All configurations are then as expected apart from La, Gd, Lu, Ac, Th, Pa, and probably 6d elements. Double sharp (talk) 14:41, 13 November 2022 (UTC)


 * Thanks. Here are some initial comments.


 * I stumbled upon a chemistry stack exchange page which appears to shed some light on the question:


 * "Q: Are the elements La and Ac considered to be in the d block or the f block of the periodic table?


 * A: The real lesson here is that the boundaries between "blocks" of the Periodic Table, like the boundary between "strong" and "weak" acids or bases or even between what is a stable compound and what isn't, is not sharp. Some other examples of a rough, spotty, changeable real world:


 * Most simple magnesium compounds, even the best known hydride and boride compounds, are primarily ionic, but when they have covalent character the magnesium often bonds tetrahedrally as if using 3𝑝 as well as 3𝑠 valence orbitals. See for instance the coordinated structure given here for methylmagnesium chloride in THF. Beryllium shows this effect even more prominently in its wider variety of covalent compounds.


 * Calcium could be called a 𝑑-block element when it bonds with its 3𝑑 orbitals in this calcium(I) compound (and yes it is +1, showing multiple oxidation states like a transition element).


 * Cerium, the second element is the lantanide series, does some straddling of its own between 𝑑 and 𝑓 blocks as its valence in the metal is changeable between 3 (with a core-like 5𝑓 electron) and 4 (with this electron engaged in the bonding). See Johanssen et al. 2 and the WP article citing this reference.


 * Among the actinides there is also thorium, which appears to involve only 7𝑠 and 6𝑑 valence electrons in the gas phase but brings in 5𝑓 orbitals in the metal (see this answer and the references therein).


 * References


 * 1. Krieck, Sven; Görls, Helmar; Westerhausen, Matthias (2010). "Mechanistic elucidation of the formation of the inverse Ca(I) sandwich complex [(thf)3Ca(μ-C6H3-1,3,5-Ph3)Ca(thf)3] and stability of aryl-substituted phenylcalcium xomplexes". Journal of the American Chemical Society. 132 (35): 12492–12501. https://doi.org/10.1021/ja105534w.


 * 2. Johansson, Börje; Luo, Wei; Li, Sa; Ahuja, Rajeev (17 September 2014). "Cerium; Crystal structure and position in the periodic table". Scientific Reports. 4: 6398. Bibcode:2014NatSR...4E6398J. https://doi.org/10.1038/srep06398."


 * On a related note Sanderson (1960, p. 8) wrote:


 * "If a d electron, for example, can easily behave like an f electron, or vice versa, the argument as to the exact ground state configuration becomes relatively unimportant."


 * That is to say, both La and Lu can relatively easily behave as if they were f elements never mind their 4f05d16s2 and 4f145d16s2 formal configs.


 * Sanderson RT 1960, Chemical Periodicity, Reinhold, New York


 * The chemistry stack exchange response and Sanderson show that the presence of this or that kind of electron, especially in marginal cases at the borders of putative blocks is less than a major consideration.


 * 1a., 4. On groups 2 and 12, I suggest there is more to the question than a single property. In periodic law terms, Be-Mg fit better over Ca by a margin of 12.5% based on Z plots for 39 properties (21 chemical, 18 physical).


 * For chemical properties, the margin is 18.5% towards group 2, with 16 properties in favour, two too close to call, and three favouring group 3.


 * For physical properties, the margin is 12.5% towards group 2, but here’s the rub: only 7 properties favour group 2, while 11 favour group 12.


 * What is happening is that the 11 physical properties which favour group Be-Mg over Zn do so by an average margin of 13.2% whereas the seven physical properties that favour Be-Mg over Ca do so by an average margin of 43.3%.


 * 1b. On the nature of group 4, while groups 1–3 feature a predominately ionic chemistry, groups 4–5, for example, exhibit predominately covalent behaviour (Greenwood and Earnshaw 1998, pp. 948, 958). Please also see notes 31 and 32 in the Location and composition of Group 3 article. The upshot is that in the specific context of simple chemistry, a split d block is very useful. Ditto a split s block, where He is over Ne.


 * 3. On the mp of La, I recall there is at least one explanation that does not rely of f-electron presence. It is in our long WP thread somewhere. Recall that GS wrote, "plausible models which do not involve 4f electrons, can be used to explain each of these properties alone." One such explanation may have been Goncharova, V. and Il'ina, G.G., 1984. Anomalies in the elastic properties of polycrystalline lanthanum on phase transitions under pressure. Zh. Eksp. Teor. Fiz., 86(5), pp.1708-1714:


 * "According to its position in the periodic table, lanthanum under normal conditions is an electronic analog of the d-transition metals scandium and yttrium and, even though it heads the group of rare earth metals, has no f electrons. The conduction band of lanthanum is formed by two 6s electrons and one Sd electron. Unlike its analogs, lanthanum is a relatively high-temperature superconductor at atmospheric pressure: T, is 5 K for the doutble-hexagonal close-packed (dhep) phase and 6 K for the face-centered cubic (fcc) phase. Lanthanum has an anomalously low Debye temperature and melting point. At low temperatures it has a negative coeficient of thermal expansion and a high electronic specific heat. These peculiar physical properties of lanthanum can be explained by a high density of states at the Fermi level, as is typical of d-transition metals, and by a strong electron-phonon coupling and a relatively soft phonon spectrum."
 * --- Sandbh (talk) 05:29, 14 November 2022 (UTC)

Eov 2
Re 1a: of course I know that blocks are not sharp, hybridisation exists everywhere. Nonetheless, throughout the entire table an x-block element can use x-orbitals as valence (x = s, p, d, f). Of course it will always use some other ones (unless we actually have H and He), but it will at least use that. Your examples don't contradict that. Mg uses 3p yes, but it also uses 3s. Ca uses 3d yes, but it also uses 4s. Ce uses 5d yes, but it also uses 4f. Th uses 6d and 7s yes, but it also uses 5f.

But Lu doesn't use 4f at all, and Lr doesn't use 5f at all, which is one step further.

Regarding the Sanderson quote, Sc and Y equally well act like the f-elements. They occur together with them all the time and Y fits perfectly in the late lanthanide series. Nonetheless nobody thinks that Y is an f-element, so there is more to it: presumably, it is because 4f is self-evidently out of reach for Y. Now, if that's also the case for Lu, why change the rules? People don't call the Zn group p-elements just because they mostly act like post-transition metals. And even though they don't even add a d-electron to the preceding element! The blocks are labelled by subshells, so presumably we should think about that when describing block assignment. We have other words for chemical groupings, like how "halogen" might not include astatine even though it's s2p5 just like all the others. We have a perfectly good term for the chemical aspect: "rare earth element". That includes La, it includes Lu, and it even includes Sc and Y. But there is no reason why "f-block" and "rare earth element" should be synonymous, since one is an electronic and the other is a chemical concept.

Re 1b: if this had been a reason to split blocks, then look at group 13. Al3+, Ga3+, In3+, Tl3+ can be pretty ionic, while Si4+, Ge4+, Sn4+, Pb4+ cannot. B-Al-Sc etc. has smoother physicochemical trends than B-Al-Ga. Will you now split the p-block? Or look at group 6. Cr is happiest in the +3 state, which is pretty ionic. Mo and W are happier in +6 which clearly isn't. Will you now split these apart? And look at Th vs Pa; by the time we reach Th, Th4+ is big enough that you can get really ionic compounds, but even Pa5+ isn't big enough. So shouldn't Th be considered d-block, like its configuration suggests? Al and Cr are way more common elements than La and Lu, so if people really were thinking along those lines, wouldn't they be splitting those blocks even more? But they're not. You have to go all the way to hydrogen and helium in terms of differences in chemical behaviour before anybody splits any other blocks – and even then, H over Li is still the majority. A table with Sc-Y-La and some others of these changes may make sense as a physicochemical one. But one with Sc-Y-La, but still H-Li and B-Al-Ga, doesn't make sense either way and is quite evidently not based on a weightage of physicochemical properties, but copying the old mistake in the e.c.'s of the Ln. The differences between Y and Lu are nowhere near the differences between H and Li!

Blocks are named by subshells, so they are an electronic phenomenon. Chemical considerations running over the boundaries is not generally considered a problem, e.g. it's well-known that the boundary d-block groups aren't very typical for transition element chemistry. But nobody uses the abrupt disappearance of nearly all the stereotypical transition properties between Cu/Zn, Pd/Ag, and Au/Hg to stop the d-block there (see Rayner-Canham for why Ag is more a post-transition metal) – even though it completely matches how d10 is reached at Cu, Pd, and Au. Stopping the transition elements at group 11, that can indeed be encountered; but stopping the d-block can hardly be encountered. (Even Jensen, a lone exception there, refers to a supposed lack of 3d involvement in Zn to justify ripping group 12 out of the d-block; unfortunately he appears to have overlooked earlier research there.) Again, the former is physicochemical, but the latter is electronic. Two different things.

Yes, GS said that you can plausibly explain each property alone. But only 4f explains them all together. And it's not an irrational hypothesis, since for example we both agree that Pr has 4f involvement, and all the exact same things are true for it. Dhcp, check. Low melting point, check. High coordination numbers, check. So pedagogically speaking, it seems better to adopt La as an f-element. Per Occam's razor, there's no need to multiply hypotheses when a single one explains everything you need to explain already. These things are literally all models anyway, so the concept applies. And anyway, you've already said that La can easily behave like an f-element, in reference to Sanderson; and you haven't disputed my link about bonding in LaF3 involving the 4f orbital on La. So I think we are already in agreement that some kind of 4f involvement for La is probable, which for me is the important thing anyway, although we probably still disagree on the extent of it. The precise amount is not too consequential, because the point that tipped me over is that for La such 4f involvement existed while for Lu it could not be substantiated.

Re Be-Mg-Ca vs Be-Mg-Zn, what I'm getting from what you're saying is that most physical properties support Be-Mg-Zn, but the ones that support Be-Mg-Ca do it more firmly. But that suggests that both situations have significant points to them, and that if you want some particular kind of physical PT, Be-Mg-Zn can potentially be supported.

So the way I see it is: in a chemical table, sure, you can have Sc-Y-La if that makes sense for the thing you're about to explain. Although that would quite often mandate B-Al-Sc too, go ahead and move that. Likewise, if you want to draw a table describing a property where Be-Mg-Zn is better, go ahead and show that. However, the table most people are using is clearly electronic, as can be seen from the way people talk about QM to explain blocks and Aufbau, and it being B-Al-Ga and not B-Al-Sc, and it being H-Li instead of H-F. Blocks are an approximation, yes, and the 2021 IUPAC report even says so. If you draw them as rectangles, it's not hard to believe that they are approximations. Doing a split d-block makes it look way more precise than it actually is (Wybourne has to say that Th is regarded as an actinide only "by analogy" anyway). It even makes it look like the same sort of differences are at play as they are for the only other block split – helium. We may disagree on many things here, but I hope we agree that He is a completely different order of magnitude from whatever is going on in group 3. :)

To summarise, my contention is that arguments based on specific chemical and physical data cannot conclusively decide placement, just like Scerri said – although my reason for saying so is that I don't believe that the common PT that everyone is using is based on that in the first place. We know it's not because otherwise, as I think you demonstrated, it would have B-Al-Sc as physicochemical properties strongly favour. Not to mention how H is over Li, which doesn't really make sense in terms of matching physicochemical properties, but makes perfect sense when it comes to electronics. "f-block" is an electronic rather than a physicochemical category, and so that should be justified electronically. In an electronic PT, then Lu, an element without valence f-involvement, cannot be an f-element, whereas La, an element with some, can be. Arguments based on physics and chemistry are instead relevant to physicochemical PT's, which are very interesting, but not the one under consideration. Double sharp (talk) 15:45, 14 November 2022 (UTC)

P.S. Since you've listed excitations that you believe are chemically feasible, let's compare the levels from NIST.


 * Be 2s2 → 2s12p1: 2.724963 eV


 * Mg 3s2 → 3s13p1: 2.7091049 eV


 * Ca 4s2 → 3d14s1: 2.5212633 eV


 * Th 6d27s2 → 5f16d17s2: 0.966490959 eV

It seems strangely inconsistent to believe in the first three of these and not in:
 * La 5d16s2 → 4f16s2: 1.884167 eV.

I'll grant you that Ac is more of a stretch:
 * Ac 6d17s2 → 5f17s2: 3.873287 eV.

On the other hand, it's generally agreed that transition metals can use the p-orbitals for hybridisation, and look at this:
 * Pd 4d10 → 4d95p1: 4.2240148 eV.

So there seems to be no reason to doubt that La and Ac have f-orbitals within normal chemical ionisation ranges.

For Yb, at least we have:
 * Yb 4f146s2 → 4f135d16s2: 2.8750098 eV.

For Lu, the first level I can find breaking open 4f at all has to do triple ionisation first:
 * Lu3+ 4f14 → 4f135d1: 11.21225 eV.

This is beyond even the strongest bond energy known for a neutral molecule (C≡O 11.16 eV), suggesting that it's not chemically feasible.

At least for Zn, we only need one ionisation:


 * Zn+ 3d104s1 → 3d94s2: 7.776593 eV.

More or less comparable with an alkene C=C bond energy.

For Ga, forget about it:


 * Ga2+ 3d104s1 → 3d94s2: 16.166989 eV.

Hopefully this very long response is interesting to chew on. :) Double sharp (talk) 21:54, 14 November 2022 (UTC)


 * Thanks for your extensive and interesting response.


 * Item 1a
 * You wrote, "...throughout the entire table an x-block element can use x-orbitals as valence (x = s, p, d, f)."


 * Is that 100% right? Does it apply to every member of the f-block?


 * As to Sc and Y as f-elements my position is (as set out in my peer-reviewed article in FoC) that it is the most important orbital that influences the positioning of an element. Hence La is d-block and Lu is f-block given La is not subject to the f-induced Ln contraction whereas Lu is.


 * Re "Y fits perfectly in the late lanthanide series" I tend to doubt this. Recall Restrepo found that in stoichiometric terms, La fitted best with Y rather than Lu. And here is what I wrote in the FoC article:


 * "In terms of chemical separation behaviour, that scandium, yttrium and lutetium occurred in the so-called yttrium group, and that lanthanum occurred in the “cerium” group did not imply anything particularly significant; it is simply a reflection of the increasing basicity of these elements as atomic radius increases. Taking the alkaline earth metals as another example, magnesium (less basic) belongs in the “soluble group” and calcium, strontium and barium (more basic) occur in the “ammonium carbonate group”. Moving lutetium under yttrium because they occur in the same chemical separation group failed to consider separation group patterns elsewhere in the periodic table.


 * Further, the separation group behaviour of yttrium can be ambiguous, and scandium, yttrium, and lanthanum appear to show complexation behaviour different to that of lutetium. As observed by Vickery (1960, p. 37):


 * In separating yttrium from the heavy lanthanoids, advantage is always taken of the phenomenon by which yttrium sometimes assumes characteristics similar to those of the light lanthanoids, and sometimes follows the heavy lanthanoids in behaviour.


 * Over a decade later Vickery (1973, p. 344) observed that:


 * Polymerization of the yttrium ion has been shown now to account for its apparently nomadic behaviour in earlier classical separation techniques. Evidence is also available for the existence of lanthanum hydroxy-polymers in solution. There is, indeed, to be seen an interesting sequence through…Group III in this respect. Hydroxyl bridged polymerization has been shown for aluminium, scandium, yttrium, and lanthanum ions, but does not appear to exist with the series Ce3+ → Lu3+. On the other hand, gallium, indium and thallium do appear to complex in this fashion. On a thermodynamic basis, ionic hydration—or hydroxo complex formation—may depend upon free energy rather than enthalpy and plots of such free energy link the pre-lanthanon triad more closely to aluminium, on the one hand, and gallium, etc., on the other, than to the lanthanoid group of elements.


 * The chemists who kept lanthanum under yttrium were on the mark, chemically speaking."


 * Item 1b, and group 13 specifically:
 * boron is characterised by covalent chemistry;
 * aluminium bonds covalently in most of its compounds (Cooper 1968, p. 25; Henderson 2000, p. 9);
 * ditto gallium (Walker, Enache & Newman 2013, p. 38);
 * the tendency of indium "...to form covalent compounds is one of the more important properties influencing its electrochemical behavior" (Liang, King & White 1968, p. 288);
 * for thallium, although compounds in the +1 (mostly ionic) oxidation state are the more numerous, it has an appreciable chemistry in the +3 (largely covalent) oxidation state, as seen in its chalcogenides and trihalides (Howe 1968a, p. 709; Taylor & Brothers 1993, p. 131; Lidin 1996, p. 410; Tóth & Győri 2005, pp. 4, 6–7).


 * This explains why group 13 has not resulted in a p-block split. The citations are from our post-transition metal article.


 * Nature of the table, pt 1
 * I think the current periodic table with H over Li; He over Ne; group 3 as Sc-Y-La-Ac; and B-Al- over Ga is a "combo" table, based on a mix of historical, didactic, pragmatic, electronic and physicochemical considerations.


 * This explains why one with Sc-Y-La, but still H-Li and B-Al-Ga makes sense, so to speak.


 * Blocks
 * Blocks are indeed named by subshells but that does not limit their scope to electronic phenomena.


 * 4f to rule them all?
 * I'm happy that GS explains how 4f can explain all the properties together but unhappy that his theory is unconfirmed.


 * 4f in La
 * I agree 4f involvement occurs, at the margins.


 * Nature of the table, pt 2
 * The table most people use is not electronic. It is rather a classification based on the several considerations I noted above. Hence it accommodates He over Ne.


 * General thoughts
 * I suggest the chemistry stack exchange Q&A goes a fair way to explaining why the IUPAC group 3 project concluded there was no objective way to adjudicate the issue.
 * I think that each of the two options has something to offer, and that each comes with advantages and drawbacks.
 * I reckon that for the 85 years post- Meggers and Scribner (1937), nobody had been able to mount a sufficiently compelling case for changing from Sc-Y-La-Ac to Sc-Y-Lu-Lr, bearing in mind La was discovered in 1839 and Lu in 1907.
 * --- Sandbh (talk) 05:09, 15 November 2022 (UTC)

Eov 3
1. Yes, it is 100% right. The Chinese paper I mentioned shows direct bonding of the 4f orbitals all the way up to Yb. You do need very electronegative O and F as the ligands, true. And moreover, the configuration of almost all the Ln is fxs2, but the configuration of the Ln3+ ion is fx−1. Clearly the f-subshell has been dug into, and since +3 is usually the most common oxidation state, there you have it. If you're asking about 5f, then I don't have complete computations all the way to nobelium, but I think the reasons for that are obvious. Besides, No [Rn]5f147s2 can (if reluctantly) ionise to No3+ [Rn]5f13, which is good enough for me.

2. I don't agree that f is the most significant orbital for Lu. It is not valent. All it does is act as incomplete shielding. Hf–Hg are in the exact same position: they are clearly filling the d-shell, and all the f-shell actually does is act as incomplete shielding. An orbital that takes 11.21225 eV of energy to actually ionise is clearly not the most significant for chemistry, compared to the d subshells of Lu that obviously do something.

3. The things you mention for Y strike me as side issues. In all of geochemistry yttrium acts exactly like a heavy rare earth. It is always found in combination with them. Lutetium was literally found in ytterbium, which was literally found in erbium, which was literally found in yttrium. The fact that we can force it to act differently in environments we rather than Nature create is a sideshow to that. Probably the only one where I'd agree the relationship is about equally good for either side is Gd, which was discovered in 1886 in both yttria and ceria. I agree anyway that the separation group difference is not conclusive, because you first have to see if radius should really increase down group 3 or not. But that amounts to asking if 4f is completed before or after group 3. Which amounts to going back to the subshells. Which goes back to the answer that tipped me over: La can apply 4f, Lu cannot apply 4f.

4. I don't see any reason to believe that 4f involvement for La is "marginal", considering that it explains many things, its existence has been clearly calculated in LaF3, and the excitation energy needed is lower than for excitations you accept without reservation (the ones that appear in that Chemistry Stack Exchange post). This last point especially is why I wonder why you have such problems accepting it, really: doubting La 4f which is 1.88 eV above the ground state, but accepting with open arms Be 2p which is at 2.72 eV, does not seem to make much sense to me. And anyway, even "marginal" 4f involvement for La is okay for me considering that 5f involvement for Th, by the evidence you seem to be admitting for La, is equally marginal: the only justification you have for it is Th3+, which doesn't occur in aqueous solution, doesn't occur even as an iodide, and when it finally does occur in some organothorium compounds, it's not even 5f1 anymore, but 6d1. And also because there's still no 4f involvement for Lu at all, so any 4f involvement for La, however marginal, is a step up. Seriously, by your arguments a Landau-and-Lifshitz-style table with both La and Lu under Y would make more sense. We both agree that Lu has no significant f involvement.

5. I don't think you can easily cleave ionic from covalent that way. I seem to recall we had some exchanges on this in 2020. Although I think my tone was too harsh, I still stand by the scientific content of this post: Look, there is no such thing as a complete volte-face from ionic to covalent. It depends on what the counter-anion is. We go from ionic to metallic (which you're overlooking completely) across the series NaCl, Na2O, Na2S, Na3P, Na3As, Na3Sb, Na3Bi, Na. And that's in group 1, with an example taken straight from Greenwood & Earnshaw p. 81. Ionic vs. covalent is (1) gradual, from covalent to polar covalent to mildly ionic to strongly ionic, depending on the difference of electronegativity between the two elements; (2) not a complete dichotomy, because you overlook metallic bonding; and (3) not split by elements, but rather by electronegativity differences, which have a lot to do with oxidation state (just compare uranium chemistry as we jack the oxidation state up from +3 to +4 to +5 to +6). So I'm astonished to see you put so much weight on "ionic vs. covalent" as a false dichotomy. (And as I keep saying, the general thing across the periodic table is continuity, and the sharp dichotomies you like to point to have a distinct tendency to not exist.) The whole literature, when it sees fit to split "main group" from "transition", universally uses other criteria like "variable oxidation states", "coloured compounds from d–d transitions", "a wide variety of complexes", "formation of paramagnetic compounds". Ionic vs. covalent has nothing to do with it, and nobody uses that as a criterion in the literature for this divide. Respectfully, I put it to you that Zr, Hf, Nb, and Ta by this standards have weak credentials as transition metals, just as weak as Sc for that matter. And here's some points from Rayner-Canham & Overton that appeared later in the discussion: Unfortunately, there is no firm predictable boundary between ionic and covalent behaviour for solid compounds of metals and nonmetals. As predicted from Fajans’ first rule, increasing theoretical cation charge results in increasing charge density, which will favour covalent behaviour. However, as predicted by Fajans’ second rule, the anion also plays a role: thus as the metal oxidation state increases, the iodide is first likely to exhibit a low melting point, then the bromide, then the chloride, and finally the fluoride and oxide. (p. 99), inorganic chemists see not a rigid ionic-covalent divide but a bonding continuum. Figure 5.11 shows electron density profiles for four points on this continuum: the pure covalent, a polar covalent bond, a polarised ionic bond, and a pure ionic bond. The ratio of ionic to covalent character can be defined as the difference in electronegativities…between the pairs of atoms. Thus, pairs of atoms with…[a difference] close to zero will possess essentially pure covalent bonds with equally shared electrons, whereas those…> 3.0 are regarded as purely ionic… (p. 109). Then they refer to the triangle of ionic, covalent, and metallic bonding. Indeed, Al and Cr are if anything "predominantly metallic bonders", as that's what they'll do with most of the periodic table! I suspect all your sources have some kind of context being set way outside of this (maybe something like "no intermetallic compounds"), but then they are ignoring a significant part of chemistry. And how would you treat the chalcogens? O is mostly covalent when bonding with nonmetals, and mostly ionic when bonding with metals. So I still don't think it makes that much sense to me. Respectfully this time, of course.

5a. And anyway, H-Li is still a pretty golden example. Li+ is, well, obviously ionic, like all the bigger ones. H+ is, well, obviously not. You have a golden opportunity to move it to over F and, if I remember your investigations correctly, that improves physicochemical smoothness. So why is hardly anybody taking that up? Clearly the PT is more to the electronic side of affairs than you admit. I mean, even He over Ne is sometimes justified not as "we keep the noble gases together", but "the shell is full".

6. If blocks aren't specifically an electronic concept, then why are they named like that? What exactly makes the Zn group d-block? Seems pretty clearly electronic there, since they have not very much in common with the rest of the transition metals. Even better, what exactly makes H and He s-block?

7. I think what is more likely to explain the starting statement of the project is what Scerri wrote himself in The Periodic Table: its Story and its Significance: different physicochemical properties suggest different answers to the group 3 puzzle. Hence the need for something more fundamental.

7a. As Scerri has been recently stressing, QM almost completely explains the PT from first principles. As such, an electronic table has a significant gain on all physicochemical tables: it has the opportunity to explain so much more, and you can read into it trends that are not directly there. For example, you don't even lose Sc-Y-La in an electronic table, because you can easily see that they are all three elements from the left, and so they are all three electrons above a noble gas core, and so they share a secondary relationship. Ditto B-Al-Sc. Whereas in a physicochemical table, how exactly am I supposed to read Sc-Y-Lu into it if it's not already there? That even provides another argument I think I've mentioned: in an 18-column Sc-Y-Lu table, you can align La and Ac in the footnote under Sc-Y-Lu-Lr, and outright make the secondary relationship explicit. Then it lines up perfectly with how Ce and Th are "group 4-ish", Pa is "group 5-ish", etc. Whereas if you try it in Sc-Y-La, then Lu and Lr get lined up with group 17, which is not useful. A secondary relationship, that was explicitly there, has been lost.

8. The Sc-Y-La table doesn't even properly reflect the one property where the Madelung anomaly of La and Ac not filling f is important (spectroscopy of the ground state): Th is still stuck in the f-block without f electrons, and Lu and Lr are still stuck in the f-block without valence f electrons. Landau and Lifshitz's idea of La and Lu both outside the f-block at least makes more sense for that, and would make me like it more. But that is something different. Why not just have Sc-Y-Lu, align La-Ac under group 3 in the footnote, like we currently have, and say: hey, we still have all the elements we want in the same column. If we made it Sc-Y-La with Lu-Lr under group 17, we don't have that. For that reason alone Sc-Y-Lu is clearly better IMO, because everything that can be read from Sc-Y-La can also be read from Sc-Y-Lu-Lr(-La-Ac in the footnote, with vertical alignment preserved), whereas that's not true the other way round. Hopefully, interesting food for thought. :) Double sharp (talk) 10:13, 15 November 2022 (UTC)
 * Ds: in an 18-column Sc-Y-Lu table, ...&mdash;no. That's abuse not compromise. The need you describe is adding "xC" groupnumbers, similar to introducing xA and xB when we went from I-VIII-0 Reihen to IA-VIIA-VIII-IB-VIIIB-0 groups (from Mendeleevs 1871/1900 short form to the pre-1940 long form). Also, we should rename E94. DePiep (talk) 07:05, 16 November 2022 (UTC)
 * You mean like the Antropoff-Scheele version? Double sharp (talk) 11:33, 16 November 2022 (UTC)
 * Just xC-group numbers to be in the "n/a" columns, I guess. As a detail of your post. (Of course, renumbering 1–18 now bites us; but your point can be shown in earlier ones). File under: "Never require 18-column PT to make your point".
 * Don't know yet how AvonA's 1926 structure pans out re Pluto (should he be credited with pointing out the error?). Lots of research to do. DePiep (talk) 11:50, 16 November 2022 (UTC)




 * 1. The abstract of the Chinese paper says:


 * "The Ln 4f orbitals do not directly participate in bonding from the view-point of traditional bonding theory..."


 * OK; that's interesting.


 * "...but may influence the bonding to a certain extent through mixing a little match orbitals into the localized 4f orbitals and mixing some 4f component into the delocalized molecular orbitals, causing the bond lengths shortened and the bonding energy increased by about several hundredths in general."


 * OK; so we are talking about several per cent.


 * On page 1380 (right column) they say there is almost [bold added] no difference for Lu vis à vis f participation, i.e. there is some f participation.


 * Now, Table 1 shows that the difference in calculated bond lengths for frozen 4f v unfrozen 4f is CeS 0.011; EuS 0.005; GdS 0.003; YbS 0.002; LuS 0.001. Table 2 shows that the difference in calculated bond energies for frozen 4f v unfrozen 4f in CeO is 2.42 (eV); EuO 1.06; GdO 1.03; YbO 0.58; Lu 0.07 (i.e. 7%).


 * So there is some 4f involvement in the Lu compounds.


 * Table 3 shows that 4f contribution to the bond level for frozen and unfrozen 4f is CeO 0.065:0.065; EuO 0.017:0.033; GdO 0.012:0.045; YbO 0.008:0.008; Lu 0.007:0.007.


 * Either way, Lu has some 4f contribution.


 * In the conclusion the authors write: "In Lu compounds 4f orbitals basically [bold added] have no contribution to bond formation." That is to say, they did not write, "In Lu compounds 4f orbitals have no contribution to bond formation" because they couldn't.


 * 2. I didn't write that "f is the most significant orbital for Lu."


 * Instead, here's what I wrote:


 * "As to Sc and Y as f-elements my position is (as set out in my peer-reviewed article in FoC) that it is the most important orbital that influences the positioning of an element. Hence La is d-block and Lu is f-block given La is not subject to the f-induced Ln contraction whereas Lu is."


 * For La, the most important orbital is d. For Lu, the most important orbitals are f (the poor shielding of which results in the Ln contraction) and d.


 * 3. That La fits better under Y than Lu on e.g. stoichiometric grounds, per Restrepo, does not strike me as a side issue. It certainly wasn't for DIM. Simon Cotton and team's recent article noting zero support for shifting Lu under Y is the same.


 * I further wrote in my article:


 * ”For example, since yttrium is commonly found in nature together with the heavier lanthanoids including lutetium it is sometimes argued that this supports Group 3 as Sc-Y-Lu-Ac (Thyssen and Binnemans 2011, p. 80). In fact yttrium is unique among the rare earth elements in that, depending on the circumstances, it can behave like a light lanthanoid e.g. Pr, Nd, Sm, or a heavy lanthanoid e.g. Dy, Tm, Lu (Marsh 1947, p. 1084; Jowsey et al. 1958, p. 64; Bünzli and McGill 2011, pp. 19, 26; Gupta and Krishnamurthy 2005, p. 165). In terms of the stoichiometry of binary compounds, yttrium is reported to be more like lanthanum than lutetium (Restrepo (2018, pp. 94–95). In a similar vein, lanthanum has a sufficiently distinct nature compared to the cerium to lutetium series (Liu et al. 2019).”


 * 4. I acknowledged La 4f involvement in my FOC article (note 29). That said, this is not of the same magnitude as occurs in Ce to Lu, by way of the Ln contraction, which starts at Ce and peaks at Lu.


 * 5f is present in Th metal, and explains its crystalline structure.


 * 5. The ionic v covalent distinction is a useful rubric in chemistry, as relied on by the several authors cited in my peer-reviewed article. As expressed by Nelson (2011):


 * "…care needs to be taken to remember that…[this classification scheme] is only an approximation, and can only be used as a rough guide to the properties of the elements. Provided that this is done, however, it constitutes a very useful classification, and although purists often despise it because of its approximate nature, the fact is that practising chemists make a great deal of use of it, if only subconsciously, in thinking of the chemistry of different elements.


 * While Nelson was referring to a scheme for classifying the nonmetals according to their electronegativity, the principle is the same.


 * 5a. Li is over H on account of a mix of historical, didactic, pragmatic, electronic and physicochemical considerations.


 * Yes, different physicochemical properties suggest different answers to the group 3 puzzle. Hence there are other considerations, including electron configurations.


 * If the PT was truly electronic then Scerri and Parson’s argument…


 * "For the purpose of selecting an optimal periodic table we prefer to consider block membership as a global property in which we focus on the predominant differentiating electron.” (Scerri and Parsons 2018, p. 151)


 * …supports La in group 3, since such a table has one less differentiating electron discrepancy than an Lu table.


 * 6. I didn't say:


 * "blocks aren't specifically an electronic concept."


 * Instead, what I wrote was:


 * "Blocks are indeed named by subshells but that does not limit their scope to electronic phenomena."


 * I had in mind what Philip Stewart wrote:


 * "The division into blocks is justified by their distinctive nature: s is characterized, except in H and He, by highly electropositive metals; p by a range of very distinctive metals and non-metals, many of them essential to life; d by metals with multiple oxidation states; f by metals so similar that their separation is problematic. Useful statements about the elements can be made on the basis of the block they belong to and their position in it, for example highest oxidation state, density, melting point… Electronegativity is rather systematically distributed across and between blocks."


 * 7. Re: "different physicochemical properties suggest different answers to the group 3 puzzle." Not so. Based on the smoothness of 40 physicochemical trendlines, La is a better option by 6.0%. That said, it is evident that the PT is based on more than physicochemical considerations.


 * 7a. QM is one more of the considerations that go into compiling the PT.


 * 8. Spectroscopy is another of the considerations that go into compiling the PT. I will grant you that La-Ac under Lu-Lr brings out a nice secondary relationship. That said, a periodic table cannot show all desirable relationships. Further, it is rather easy to maintain the secondary relationship in an La table. So, group 3 becomes 3* and another 3* is placed over Lu-Lr. The asterisk note then reads: "Group 3 bifurcates after Y into an -La-Ac tranche and an -Lu-Lr tranche. Sandbh (talk) 06:22, 17 November 2022 (UTC)

Noname (so far) break

 * OK. I feel like we both understand our positions well, and it seems to me that they are based on sufficiently different premises that the arguments that convinced each one of us will clearly not convince the other. So I think this is a good enough stopping point for this exchange of views at present. :) Double sharp (talk) 11:24, 17 November 2022 (UTC)
 * Thanks. As I now see it, each of the two options has something to offer, and each comes with advantages and drawbacks. So it is not about convincing one another that the other's option is better. Same goes for the various proponents over the years of Lu-Lr, none of whom considered the drawbacks of Lu-Lr or examined the pro's and con's of La-Ac, AFAICR. Ditto La-Ac proponents although I did briefly discuss Lu-Lr in my FoC article. It is no wonder the IUPAC group 3 project found there was no objective way to decide and that IUPAC as a whole, according to Eric, seems to be prevaricating. Is that how you see it? Sandbh (talk) 01:09, 18 November 2022 (UTC)

As I see it, both classifications have some chemical and physical reasons favouring them, but I agree with Scerri's point that chemical and physical arguments are inconclusive because some go one way and some go the other way.

Additionally, I think the table is far more based on electronics than you think, based on textbooks generally introducing the PT through the subshells and the historical development from Bohr onwards; and I consider an electronic table to be fundamental because QM is the underlying basis for all chemical and physical properties, even if we cannot do all the calculations yet needed to do such a first-principles derivation.

I also agree with Scerri's philosophy that the classification is one of elements as abstract substances (most usefully identified with atoms) and not as simple substances, and so I consider that the only properties that really count is what's preserved of the element across all chemical transformations, i.e. the atomic number and the valence manifold.

Finally, I also think that the entire thing is a model, and that by Occam's razor, it is better to choose the simpler model when possible: pedagogically it seems better to me to start with a simple model and then add complexities, rather than present all complexities at once.

To me the PT is just a projection of the landscape of all properties that can exhibit periodicity, and the question is what convention to choose as most useful, which to me is the one that lets you explain the most stuff i.e. electronics.

That supports Sc-Y-Lu for the reasons given by the project and a reason given by Jensen: it does not require splitting the d-block (which is not necessary when the rare earths are so similar, so per Occam I don't want it), it matches the QM basis (which is how we teach and explain periodicity these days), it keeps the order of increasing atomic number intact, and it ensures that f-block elements can always have f-orbital participation in chemistry (which, given the excitation energies, is quite reasonable for La but very doubtful for Lu).

These reasons do indeed also compel me to helium over beryllium, but I don't particularly mind that.

I think my position is fairly similar to Scerri's here in favour of the Janet LSPT (which I've warmed towards, though with some trepidation as the s-orbitals have energies more similar to the next n+l value usually).

These ideas will probably not work so well once the extremely blurred 8th period begins, but we build our classifications on the usually encountered cases and then extend it outward, and in any case we have a long way to go before it starts failing (maybe 139, which may still have g-involvement even though the g-block ought to have already ended; an element is discovered roughly every three years, and 139 is 21 elements away, so by this logic we can think about it again in 2085, which is a long way away).

Does this helpfully clarify what I think? Double sharp (talk) 01:32, 18 November 2022 (UTC)
 * Yes, thank you; nicely and helpfully put.


 * In what follows I use the term "you" for convenience rather than in an unfriendly or pejorative sense.


 * You remain focused on the Lu option’s perceived superiority without considering the La option and stepping back and looking at both options.


 * OTOH, and to their credit, the IUPAC Group 3 project team appear to have looked at both options and concluded there is no objective basis to adjudicate between the two.


 * All the reasons you give have counter considerations in support of La-Ac.


 * For example, I agree electronics is an important consideration. This being so, and as you know, I have quoted Scerri and Parsons (2018, p. 151):
 * "For the purpose of selecting an optimal periodic table, we prefer to consider block membership as a global property in which we focus on the predominant differentiating electron.” [Exhibit A]
 * Their approach supports La in group 3 since such a table has one less differentiating electron discrepancy than an Lu table.
 * Further, each block in such a table starts with the appearance of the relevant actual differentiating electron [Exhibit B].
 * Exhibits A and B are so easy.
 * The literature is also focused on an electronic approach to the periodic table. And Sc-Y-La-Ac is effortlessly accommodated within this paradigm.
 * If the matter comes down to convention (accepted usage), then the current convention is Sc-Y-La-Ac, which has a plurality of appearances according to the IUPAC project team's survey.
 * Per Reger, Scott and Ball (2010, p. 295):
 * Perhaps the correct shape of the 32-column periodic table should feature a split d block given the electron configurations of La and Ac, but that "we avoid these structures by splitting the f block from the rest of the periodic table". This also has the advantage of being able to print a legible periodic table on a single piece of paper." (They show La below Y in the rest of their book.)
 * Does this helpfully clarify yours and my thinking? Sandbh (talk) 02:45, 19 November 2022 (UTC)

Differing opinions

 * Respectfully, I'd say it rather clarifies why we have such different opinions: to you these are "so easy", but to me they are rather inconsistencies of Sc-Y-La. :)
 * Differentiating electrons are not well-defined. What is the differentiating electron between vanadium 3d34s2 and chromium 3d54s1? There isn't only one. Preferably, link to something in the literature that explains how it works for such a case, because I'm not going to be convinced if you made it up. Presumably, a PT should be based on considerations that more than one person can explain. And even then, the strangest thing about this consideration is that the "one extra" rests entirely on the Lr 7p anomaly, which is quite odd as it apparently fits neither an f-block nor a d-block placement. If Lr had had a 6d electron as everyone thought, it would be impossible to decide based on this criterion either: there would be equally many anomalies in each form. (Not that I even know what the differentiating electron is when there's more than one, but at least for La/Ac and Lu/Lr there is obviously one, so the count can be done.) So you are essentially using Lr's 7p configuration to support that it should be in the f-block, which is bizarre to say the least. :)
 * If we look at each row of the blocks, then it is very much a different story, as 5f does not appear in thorium. Given the electron configuration of Th, perhaps it should appear below Hf as it did before Seaborg, and then the actinides should follow from Pa to Rf. (After all, Reger, Scott, and Ball have to refer to Ac as well as La. If La had no f-electron, but Ac did have one, there would obviously not be a debate: just look at Ce vs Th where Th is always put in the f-block. So it is clearly not enough to just look at the beginning of the block, you have to look at every row.) By the configuration of Lr, with the first appearance of 7p, surely it should be placed below Tl and bump Nh? It's such an original anomaly, and you are sweeping it under the rug! Or look at the ends of the d-block rows: why are Zn, Ag, Cd, and Hg considered d-block elements, since the d-shells have already finished? They even all act quite like main-group elements in chemistry! By not considering each row, you are implicitly implying that the blocks should be rectangles, which is in favour of symmetry over whatever the electron configurations actually are. Early chemists and physicists suggested that the 5f orbitals might start filling after uranium (or at least later than the 4f ones started filling in the previous period), so they clearly considered each row separately. If one holds symmetry in such high esteem, why not simply go one step further and admit the use of symmetry to avoid splitting blocks? Or why not actually fit reality even better and cut the 3d row to nine elements (Sc-Cu), the 4d to eight (Y-Pd), and allow both La and Lu to be 5d elements as the configurations suggest? By not having a thirteen-element Ce-Yb f-block you are already moving from what the electron configurations suggest at face value, since the 4f subshell fills exactly over those thirteen elements only! Or look at where the g-block is supposed to begin, as Scerri has suggested. The first g-electron is not supposed to appear till element 125 or maybe 126. Except that even people using Sc-Y-La still start it at 122, further proving the inconsistency. The most astonishing case is Fricke himself, who calculated the electron configurations that far out, had a really big split in his d-block, and still started the g-block at 122. Sc-Y-Lu at least consistently treats the Madelung rule as the truth, and that's within 4 eV of it anyway, i.e. perfect modulo chemical bond dissociation energies.
 * That gets into the point that electronics should be considered across environments found in chemistry, and not just one atom sitting around by itself (which is kind of the opposite of "environments found in chemistry"). In such cases La 4f has been invoked numerous times. You couldn't possibly "experimentally confirm" a theoretical model, only evaluate it on how well and parsimoniously it fits and predicts what we see, and per Gschneidner 4f involvement for La is quite simply the most parsimonious model as nothing else explains so much. And you're quite quick to accept from Johansson et al.'s theoretical paper the valence-to-core changing of 4f for Ce, but incredibly unwilling to accept Wittig's 4f resonance for La. It seems like unexpected orbital usage for every other element is accepted with open arms, whereas only for La and Ac do you greet it with an endless stream of fear, uncertainty, and doubt. Even if it takes more energy to excite Be to occupy 2p than it does to excite La to occupy 4f (and, especially bizarrely, it takes more energy to put Ag into the Madelung-expected d9s2 configuration than it does to put La into the Madelung-expected f1s2 configuration). Why, because that's the one thing that Jensen notes really torpedoes the Sc-Y-La-Ac form? Oh, here's another one: 4f valence band mixing in LaH1.8. And one from this year: Furthermore, La mainly hybridized with coordinated oxygen atoms via 4f, 5d and 6p orbitals, while Lu hybridized via 6s and 5d orbitals, and the difference between La and four extractants originates from 5d and 6p electrons while it mainly comes from the 6s orbital for Lu. Again, 4f for La, but not for Lu. Jensen keeps getting proved right.
 * On its own the grouping of Sc, Y, La, and Ac has some justification, but consistently applying it across the entire periodic table (which you don't do) leads to a ton of unwanted consequences that nobody adheres to. While it's true that Sc-Y-Lu could be argued to consistently lead to He over Be, (1) it's not quite the same situation as even people putting He above Ne think that it is an s-element, and (2) I am fully prepared to accept He over Be anyway, as is Scerri nowadays. Some chemists working on the light noble gases (Wojciech Grochala and Felice Grandinetti) have also written in favour of He over Be, so this is at least something that people actually support, unlike "Th in group 4", "Lr in group 13", and "d-block ending at Cu/Pd/Au" that your approach forces if applied consistently.
 * Something that is accepted by less than half of all university textbooks surveyed ipso facto cannot be "accepted usage". And by the way, what's the textbook consensus on the metallicity of astatine? Or, more relevantly for the group 3 thing, the electron configuration of Lr? Considering that the latter is so important for your "differentiating electron" case for Sc-Y-La (which would collapse if Lr was 6d), it seems to be important to see if textbooks get it right or not. It's been predicted since 1971, so there is a clear date to start looking. If they can't do their homework and get something that important to your case for Sc-Y-La right, then will they truly have considered the information thoroughly when deciding on their form? :) Double sharp (talk) 12:05, 19 November 2022 (UTC)

Thanks; I'll post my thoughts one-by-one.

Differentiating electrons. With respect, it's a trivial matter to define what these are, as I did in my peer-reviewed FoC (Eric Scerri, editor-in-chief) article. I've seen at least one other published version of this explanation which I didn't take particular note of since it's straightforward. From my article:


 * "Sometimes the differentiating electron (d/e) is not immediately apparent. For example Z = 40 Zr is 4d2s2 and Z = 41 Nb is 4d45s1. Here the d/e seems to be d2s−1. In such cases the d/e is taken to be the newly added d-electron, rather than the s-electron that was already there (so to speak)."

For vanadium 3d34s2 and chromium 3d54s1 the differentiating electron seems to be d2s−1. Per the above example, it's actually the newly added d-electron.

There's more going on with d/e anomalies than just Lr.

In an La table, the d/e anomalies are d-block: Mn(s), Zn(s), Tc(s), Ag(s), Cd (s), Hg (s) = 6; f-block: Gd(d), Lu(d), Th(d), Cm(d), Lr(p) = 5, = 11 net.

In an Lu table, the anomalies in the d-block are increased by +1 with the addition of Lr(p), thus 6 + 1 = 7. In the f block, the anomalies are reduced by 2 with the absence of Lu and Lr, but increased by two with the addition of La(d) and Ac(d). Thus 5 –2 +2 = 5, = 12 net.

There is nothing bizarre about Lr (p) being in the f-block. Sandbh (talk) 05:51, 21 November 2022 (UTC)

Appearance of the relevant actual differentiating electron. It works as an easy to teach  rubric, period: "A block starts when the first electron of its name enters the applicable subshell." (14 words). There is no need to be concerned about elements later on in each block. In contrast, your explanation takes 443 words—thirty times as many. Sandbh (talk) 05:59, 21 November 2022 (UTC)

4f involvement. I acknowledge this for La in my FoC article. Please see note 29. For 4f influence/involvement in Lu please see argument VI in my article: "The different behaviour of lutetium has been attributed to an indirect effect of its 4f14 subshell."; and Ji, W. X., Xu, W., Schwarz, W. H. E., Wang, S. G. 2015, Ionic bonding of lanthanides, as influenced by d- and f-atomic orbitals, by core–shells and by relativity, ''J. Comput. Chem.'' 36, 449– 458. :


 * "Since the outer 5s-5p "semicore" as well as the inner, though open 4f 'semivalence' shells are somewhat polarizable, the question arises, which shells may be treated as frozen or better included in an extended optimized valence shell."


 * "Freezing the outer closed shells of Lu causes large errors in the bond lengths (too long) and bond energies (too small). The freezing of the outer 5s2 5p6 Xe noble-gas semicore shell is more serious than the freezing of the inner 4f14 semivalence shell. The errors of shell-freezing are approximately additive. These findings for the lutetium halides are in line with similar findings for various lanthanide oxo-compounds (carbonates, phosphates, borates, etc.)."

--- Sandbh (talk) 06:13, 21 November 2022 (UTC)

Consistently apply Sc-Y-La-Ac across the periodic table. No, there are no unwanted consequences since the periodic table is a classification and classifications can accomodate a degree of pragmatism. Not to mention didactic and historical considerations. OTOH, there are unwanted consequences in the Lu form which Lu proponents (including Scerri) overlook. --- Sandbh (talk)

Less than half of all university textbooks. There are three forms of the PT with accepted usage, the La form, the *-** form, and the Lu form. According to the IUPAC survey the appearance frequencies of these three forms are 48.5, 33.3 and 18.2% respectively. The La form is the most common of the three.

For astatine there is no controversy (only uncertainty). Qualitative and quantitative assessments of the status of astatine, since 1940, including having regard to relativistic effects, have been consistent with it being a metal:
 * 1940. Astatine was judged to be a metal when it was first synthesized. That assessment was consistent with some metallic character seen in iodine, its lighter halogen congener.
 * 1972. Batsanov calculated astatine would have a band gap of 0.7 eV (but see the 2013 entry).
 * 1983. Edwards and Sienko speculated that, on the basis of the non-relativistic Goldhammer-Herzfeld criterion for metallicity, astatine was probably a metalloid. As the ratio is based on classical arguments  it does not accommodate the finding that polonium (cf. 2006 entry following) adopts a metallic (rather than covalent) crystalline structure, on relativistic grounds.  Even so it offers a first order rationalization for the occurrence of metallic character amongst the elements.
 * 2002. Siekierski and Burgess presumed astatine would be a metal in the context of some of the properties of iodine.
 * 2006. Restrepo et al., on the basis of a comparative study of 128 known and interpolated physiochemical, geochemical and chemical properties of 72 of the elements, reported that astatine appeared to share more in common with polonium (a metal) than it did with the established halogens and that, “At should not be considered as a halogen.” In so doing they echoed the 1940 observation that, “The chemical properties of the unknown substance are very close to those of polonium.”
 * 2010. Thornton and Burdette observed that “Since elements in heavier periods often resemble their n+1 and n-1 neighbours more than their lighter congeners, eka-iodine [astatine]...was expected to be radioactive and metallic like polonium.”
 * 2013. Hermann, Hoffmann, and Ashcroft (23 citations) predicted At would be an fcc metal, once all relativistic effects are taken into account, and that it would have a band gap of 0.68 eV (cf. Batsanov) if only some of these effects were taken into account.

Likewise, for Lr, there was only uncertainty and not controversy. That Lr is thought to have a p electron has been fairly well settled for about a quarter of a century.

If Lr had in fact had a d electron, the number of d/e discrepancies would have been the same, and other arguments would have to be considered such as a block starts upon the first appearance of the relevant d/e.

In any case, all these considerations are moot per the provisional report of the project team, and it comes down to a matter of convention which, for WP, is the most common form appearing in the literature. --- Sandbh (talk) 12:03, 21 November 2022 (UTC)

Selective reading(?)

 * This strikes me as extremely selective reading. First you refer to the provisional report to call it a matter of convention, and then claim that that means we should go for a form that the provisional report says nothing in favour of. Never mind that the report is obviously suggesting a convention to adopt. Similarly, before 1988, nobody was using the groups 1–18 convention. Still it was an obvious choice to use once it was instituted. The obvious fact of the matter is that no form has a majority. Indeed, the project was formed precisely because there is no such convention: per the description, there had previously been no resolution, and published periodic tables show variation enough to puzzle students and teachers. Selectively reading and taking things out of context does not prove anything, especially when you show a clear and obvious bias in doing it, just like when you heap tons of fear, uncertainty, and doubt over f-involvement in lanthanum and actinium, and accept it without question for cerium and thorium. Never mind that the sources are equally reliable and from the literature in both cases. Double sharp (talk) 22:28, 23 November 2022 (UTC)

In fact, the provisional report says that:
 * "IUPAC should make a ruling on the question which in the final analysis is one of convention rather than one that can be decided on objective scientific grounds."

In WP the convention is to go by what the literature says, which is that the La form is the most common.

Never mind the provisional report says nothing in favour of the La form. (1) It is a provisional report. (2) There is no indication the provrep has been considered by IUPAC as whole; nor accepted by IUPAC as a whole; nor published by IUPAC as a whole, as an IUPAC-endorsed recommendation. (3) As EdChem wrote, and you do not acknowledge (which explains why I need to repeat it so many times):


 * "3. "WP is still hampered, in my opinion, by a preliminary report with recommendations / suggestions inconsistent with RS, that does not yet have the imprimatur of IUPAC itself. RS like textbooks will act on this (or not) in future editions, so any new consensus on a convention will take time to evolve.


 * EdChem (talk) 23:48, 21 January 2021"

Comment: No such consensus has evolved.

And we have a fair idea, from Eric's presentation, as to why IUPAC is doing nothing.

Further, the La form is as good a convention as the Lu form. The IUPAC provrep is unbalanced in this regard. Effectively no one is concerned about a split d-block (given the rarity of the 32-column form). Thus, Reger, Scott and Ball (2010, p. 295) wrote:


 * ""perhaps" the correct shape of the 32-column periodic table should feature a split d block given the electron configurations of La and Ac, but that "we avoid these structures by splitting the f block from the rest of the periodic table. This also has the advantage of being able to print a legible periodic table on a single piece of paper." (They show La below Y in the rest of their book.)


 * Reger DL, Goode SR & Ball DW 2010, Chemistry principles and practice, 3rd ed., Brooks/Cole Cengage Leaning, Australia

Re, "before 1988, nobody was using the groups 1–18 convention. Still it was an obvious choice to use once it was instituted."

In fact it was not an obvious choice e.g. Jensen disparagingly described it as "finger-counting" and periodic tables are still published with both the old and new number schemes in the same table.

Yes, while the obvious fact of the matter is that no form has a majority, the obvious fact of the matter is that the La form is the most common.

Yes, the project was formed precisely because there is no such convention (aside from which form is the most common, which the project conveniently ignored; I can just imagine the whoopin' and hollerin' and front page treatment, if the Lu form had been found to be the most popular). Actually, the IUPAC project was not formed for the reason you wrote; it was rather formed via lobbying efforts by Scerri.

Yes, I agree, selectively reading and taking things out of context does not prove anything, especially when you show a clear and obvious bias in doing it.

I do not heap tons of fear, uncertainty, and doubt over f-involvement in La and Ac. The fact of the matter is that I acknowledged this involvement in my article.

F-involvement in Ce is so obvious and so frequently mentioned in the literature that I don't need to say anymore about it. F-involvement in Th determines its crystal structure. In any event, as I have argued for a simple rubric, it remains the case that the f-block starts with the first appearance of an f electron in Ce. --- Sandbh (talk) 06:04, 24 November 2022 (UTC)
 * You claim you don't do it, and yet you're again doing it by saying some things and not saying other things. f-involvement in Th determines its crystal structure, agreed. Funnily enough, the same is true for La (notice that dhcp never appears anywhere but the f-block), and it also determines its relatively low melting point. Yet you have attacked Gschneidner's theory as "unconfirmed", never mind that he's not the only one to suggest this and that 4f being used by La (and not Lu) as a bonding orbital has been confirmed. The f-involvement in lanthanum and thorium is of the same kind: no f-orbital filling in the individual gaseous atom, but it appears in chemical environments. It is obviously selective to allow this for thorium but not for lanthanum when both are confirmed in RS. As for the "first appearance of an f electron" criterion, I'm still waiting to see the first person pay attention to that and actually start the g-block with element 125 rather than 121 or 122. You have introduced an ahistorical assumption that all rows of a block must begin together just to selectively bring in thorium to the f-block fold: Bohr certainly didn't think that. Seaborg felt the need to appeal to evidence from the heavy actinides to create an actinide rather than a thoride series. And even after deciding on an actinide series he felt the need to admit that the 5f filling did not actually begin at thorium (10.1016/S0168-1273(05)80041-8); why, his case for an actinide series was not based on where 5f actually began, but because curium mimicked actinium so well. Your rubric has not been used historically and has not been suggested for the future: it seems to be unique to you. It's not even used by people who were on your side of the debate: even Lavelle in 2008 referred to a pair out of place in his case for La, and points out that Jensen's comparison of properties was only being done for Lu and not Lr. So he looked at the second row too. You ignore that the old group numbers are clearly unusable because to different parts of the world "group IVB" meant entirely different things. You ignore that the same sort of situation was going on with group 3, making it a nomenclature issue. (Considering that IUPAC projects standardly go through a proposal to IUPAC I wonder why you decide to call it lobbying?) And in the rest of this you simply restate your old points, already answered, and use your imagination (I can just imagine the whoopin' and hollerin' and front page treatment, if the Lu form had been found to be the most popular) to attack the IUPAC project. Double sharp (talk) 17:27, 24 November 2022 (UTC)

Lawrencium etc

 * What's bizarre about it is that your argument outright depends on Lr being 7p. If Lr was 6d, you'd have equally many differentiating electron discrepancies in each form. The two anomalies at the start of the f-block in the Lu-Lr form (La and Ac have d, not f) would get cancelled out by the two anomalies at the end of the f-block in the La-Ac form (Lu and Lr have d, not f). The fact that your argument goes through depends on Lr having a p electron and therefore being an anomaly in both forms. So it essentially is saying that Lr's p-electron configuration is totally fine when it comes to putting it in the f-block, but not fine at all when putting it in the d-block. A conclusion that indeed follows from your criterion, but which is so bizarre as to put it in serious question.
 * And here we go again with the "indirect effect" of the 4f shell of Lu. By this logic, the incomplete shielding of the 4f shell of Hf-Hg equally should be counted, as does the incomplete shielding of the 3d shell of Ga-Kr. Perhaps now we should also count 2p for Na vs 1s for Li and tear them apart, because for example this core difference matters for the ionic radius trend (it's in Siekierski and Burgess)? And I love how your quote even proves my point: Lu 4f has even less effect than 5s and 5p, which are in the xenon core!
 * My 443 words are not explaining my point, they are explaining why yours has no present (nobody waits for 125 to start the g-block) or historical (few thought it was axiomatic that the 4f and 5f rows started in the same place till Seaborg) precedent. In contrast, here is an actual explanation of my criterion: "an x-block element has valence x-orbitals". Six words. Not to mention that it's not even just my criterion, but one of Jensen's. Can you cite anybody else giving yours? The periodic table, if it is to be used in general, should be based on a criterion that more than one person cares about.
 * Applying historic and didactic considerations, let's go back to the 8-column form of Mendeleev. It will better teach secondary relationships and has all the history you can ask for. Why, in the ex-Soviet countries it's even still not uncommon (or at least, its being primary is still recent history). But we've progressed beyond this to showing the subshells.
 * You ignore Rayner-Canham (2020) concluding that At is a nonmetal from its Pourbaix diagram. And you ignore Hawkes (2010) concluding At is a nonmetal from information provided in the Gmelin handbook. And you ignore that 1972 and 1983 suggest that it is a metalloid, which is not the same as being a metal. To date there is still no clear evidence that the aqueous At(I) species is actually an aqua cation and not just protonated hypoastatous acid per Gmelin, and per Gmelin electromigration evidence suggests that it is not an aqua cation. Meanwhile, textbooks very often teach us to use periodicity and extrapolate that astatine is a black solid. Why are we allowed to deny them all by referring to the literature for At, but not when referring to the literature for group 3? Seriously, given the "halogen = nonmetal" mental block that seems to be prevalent, and given that you can actually see Sb's metallic lustre, I almost wonder if Sb is more commonly called a metal than At is. After all, the diagonal stair-step is common, and Sb appears to the left of it while At appears to the right!
 * If Sc-Y-La-Ac proponents are allowed to use "pragmatism" to avoid unwanted consequences, then surely Sc-Y-Lu-Lr proponents are allowed to use it too. So here is another double standard. But feel free to share whatever unwanted consequences the Lu form has. I suspect that in all cases I will have explained either that (1) I actually want them, like He-Be or (2) they're based on things that are irrelevant for most of chemistry. Unless it's about the 8th period, in which case I would point out that (1) we don't know much about that yet and (2) we generally base our classifications on the non-mayflies. :)
 * Both Sc-Y-*-** and Sc-Y-Lu-Lr put La in the f-block. Since denying that is pretty much the main constant behind your case for Sc-Y-La-Ac, that shows that the majority of university textbooks are against a major pillar of your case. So this is even worse than a double standard. :) Double sharp (talk) 12:15, 21 November 2022 (UTC)

Thanks for contributing to this fascinating thread.

Lr: Lr is anomalous in either case. Where Lu-Lr falls down is putting two d elements (La, Ac) in the f-block = +2 anomalies whereas moving Lu-Lr fixes only one anomaly. By this answer alone it is obvious that, according to Scerri and Parsons' global differentiating electron argument, that La-Ac in group 3 is a better solution. No, this is not the same as, "essentially...saying that Lr's p-electron configuration is totally fine when it comes to putting it in the f-block, but not fine at all when putting it in the d-block." It is rather a question of where to place Lr's p-electron configuration in such a way as to reduce the global anomaly quotient.

And please bear in mind you are arguing against me, the article peer reviewers, and Scerri as the editor-in-chief of FoC.

Of course, I understand your valence orbital argument for La and Ac in the f-block but that is not the way the arrangement of the PT has evolved, which has been largely based on electron configurations. Equally, this does not necessarily invalidate your argument.

On this point,, writes:


 * "The interaction between the zinc atom and the imine groups is mainly provided by the donation of nitrogen lone pairs to an empty 4p orbital of zinc lying in the ZnN3Cl plane to give a 3c–4e bond and is further supported by π conjugation between the orthogonal 4p orbital of zinc and the N==C π bond (vide infra)."

How does this relate to your "an x-block element has valence x-orbitals" criterion?

Indirect effect. The "indirect" effect of the 4f shell starts at Ce and peaks at Lu, and explains why Lu, which has a predominately ionic chemistry unlike Hf etc, is the least basic of the Ln. The arguments about Hf-Hg, Ga-Kr, and Na, are superfluous, unnecessary and add nothing.

The quote shows that the closed Lu 4f14 and 5s2 5p6 shells in LuX3 are not inert but influence the bonding.

443 or 6 words. The arguments I put in my article were intended to note there is more to La in group 3 than may have been appreciated, and that there is at least a prima facie case for such an arrangement, not to mention it has been the most common form for about a century, and the chemistry community at large has not seen fit to change this. The article was published in 2021 and has 13 citations. Jensen's 1982 article, which started the controversy, has 116 citations = 2.9 per year. As Scerri pointed out, Jensen was rather selective in his arguments so there is nothing so significant about the fact that he may have cited an argument that matched yours.

History and didacticism. I feel that one needs to apply a broader set of historic and didactic considerations, rather than just the one example of the 8-column form of Mendeleev.

GR-C: He writes, "Often identified as a metalloid or even a metal, the predominance of evidence is that At is a nonmetal [1, 2]." His first reference is to Hawkes (deceased). I discussed the At question with Hawkes in 2010 and he conceded it would be better classified as a metalloid (Vernon 2013, p. 1704). The second reference says nothing about the metallic or nonmetallic nature of At, that I could see.

For the Q&A in the 2006 4th ed. of GR-C's book Descriptive Inorganic Chemistry, he wrote:


 * "17.29 As iodine can almost be classed as a semimetal (e.g., it is known in the +1 oxidation state), we would predict At to start to show some metallic properties: thus the diatomic element might be a significant metallic electrical conductor[!]...In fact, being so near the metal/nonmetal border, At will probably have a significant cation chemistry, forming, perhaps, At+ and At3+."

1972 makes no mention of At being a metalloid, that I could see. 1983, as I wrote, speculated At was probably a metalloid. Their work was based on a non-relativistic criterion and they would've been on target but, as 2013 showed, once all relativistic effects are taken into account At becomes an fcc metal. Further, as you wrote earlier on this (my talk) page:


 * "Something mighty interesting in this historical review that I haven't yet followed up: Since elements at heavier periods often resemble their n+1 and n-1 neighbors more than their lighter congeners, eka-iodine also was expected to be radioactive and metallic like polonium. So apparently the early workers probably had the right idea all along! Double sharp (talk) 14:06, 13 September 2021 (UTC)"

Gmelin (1985, 1984) is nigh on four decades out of date. For At+ see 2010 and 2022  which extends the stability range of At+ even further.

Textbooks vary on their expectations of what astatine would look like: I have read nearly black/black/metallic, grey. Bearing in that mind iodine has a metallic appearance under white light, they all seem to be in the same ballpark.

You can actually see germanium's lustre too but since when has a semiconductor been elevated to a metal?

The thing about the stair-step line is that (a) it is approximate; and (b) metalloids, for those authors that recognise metalloids, are found to either side of it, and here "to either side of it" does not necessarily mean all elements to either side of it.

Yes, Sc-Y-Lu-Lr proponents are allowed to invoke pragmatic considerations such as He over Ne. The unintended or overlooked consequences of the Lu form are set out in my article.

Sc-Y-*-** and Sc-Y-Lu-Lr are not comparable. The first arrangement emphasises similarities among the 15 Ln, making it "nonsensical" to refer to the 15 of them as f-block. Further, the Sc-Y-*-** arrangement makes no decision about whether either La or Lu goes under Y. --- Sandbh (talk) 06:06, 24 November 2022 (UTC)

Lawrencium (cont.)

 * So your case is still founded on the electron configuration of one extremely rare radioactive (Lr), never mind that it fills 6d in chemical environments, never mind that the "correct" 6d configuration is only at 0.1650 eV, and never mind that most textbooks get the configuration of Lr wrong. The second is also especially interesting because it seems like only for Th do you start appealing to chemical environments. Thorium is indeed an especially embarrassing anomaly for the Sc-Y-La form, but that doesn't legitimise double standards. Likewise for the fourth point, since it seems like only for La and Ac do you ever look at textbooks and come up with odd arguments to turn a textbook disagreement into a "convention". Go to astatine, and suddenly it's allowed to ignore them!
 * I further note that the 2015 article of Jensen was also published in Foundations of Chemistry. Journals can publish opposing viewpoints, as is completely obvious from the fact that JChemEd published both Jensen and Lavelle. So I am only arguing against you and not against the reviewers or Scerri.
 * The arrangement of the PT has obviously evolved in favour of valence orbitals. Otherwise, nobody would be putting Th in the f-block, because free Th atoms in the gas phase do not have f electrons. The 2021 IUPAC report even refers exactly to the thorium problem when noting that block assignment is an approximation. It's telling that even you resort to valence orbitals, referring to thorium metal's crystal structure. But somehow this is forbidden for La and Ac. So this quote from Jensen 2015 is exactly relevant: When it comes to the question of why La and Ac should remain in the d-block rather than being reassigned to the f-block, Lavelle offers no new chemical or physical evidence other than his constant reiteration of the fact that both elements contain d-electrons in their ground-state valence configurations, but no f-electrons. Yet in the cases of both Lu and Th, for which this is equally true, he proceeds to inconsistently argue that this fact is of no consequence when it comes to assigning them to the f-block. Only this time it's not Lavelle, it's you.
 * There's nothing wrong with Zn having 4p as a valence orbital; all the transition metals have np (normal in hybridisation schemes). I said that an x-block element has valence x-orbitals. I did not say that an x-block element has only valence x-orbitals, just that it has to have at least those. I did not say that because that statement is not true for anybody but H and He (and maybe some weird superheavies). And surely you know that given orbital hybridisation or MO theory. And the quote did not say that the 4f, 5s, and 5p orbitals in lutetium's core actually engaged in any bonding overlap, which is the key there. The 1s vs 2p core difference of Li vs Na equally well affects ionic radii, which is exactly the same as how core 4f affects the radii of Lu–Hg; that still does not make them anything more than core electrons, including for Lu. Valence electrons are pretty much by definition more important for chemistry than core electrons.
 * In Scerri's The Periodic Table: Its Story and Its Significance, he only points out the selectivity of Jensen's chemical and physical case for La. And he chooses his words carefully, talking about the inconclusive nature of arguments based on specific chemical and physical data. He has nothing to say about Jensen's electronic argument from 2008: After all both elements have low-lying empty f orbitals, which is more than can be said for Lu and Lr.
 * I'm not particularly convinced by the considerations you mention in your article. The very first one is already a good explanation of why: you are essentially saying that La must go under Y because it's the first d1 (Lu is only the third). By that logic, Lr must go under Tl, since it's the first p1 (Nh is only the second). Jensen already mentioned this in 2017. So this is rather a case of Sc-Y-La showing consistency problems again: why are only those two Madelung exceptions treated as special? And not Th right next door?
 * The 2010 and 2022 articles do not consider H2OAt+ (protonated hypoastatous acid, as Gmelin suggests) as a possible AtI species. This is rather an obvious omission given that protonated hypoiodous acid also exists. Germanium is a distraction; we were talking about antimony, which is actually physically a metal (OK, semimetal, but that never stopped anyone from considering bismuth) and which I suspect would be more often considered a metal by textbooks than astatine. Since At+ per se as an aqua complex is doubtful, and we only have AtO+ (and maybe even that is At(OH)2+ anyway per Gmelin, protonated astatous acid), it makes a good analogue to "SbO+" = Sb(OH)2+ anyway. One would naturally expect a knight's-move relationship between Sb and At. Rayner-Canham is citing an article on the At Pourbaix diagram, which suggests that he thinks it's more characteristic of a nonmetal than of a metal. As far as chemistry goes, frankly I agree with him: Sb has better chemical metallic credentials than At, because it doesn't appear as plain aqueous anions whereas At does. I agree personally that we should say that astatine is probably a metal in the looser physicists' sense, like arsenic and antimony; but saying that implies you have to throw out tons of textbooks as unreliable compared to an actual calculation. Which somehow you're willing to do for classifying astatine but not for placing the rare earths in the table (including comparably fugitive Lr). Double standard.
 * The IUPAC report specifically says that Sc-Y-*-** creates 15 f-block elements in each row. So once again you are reading the sources selectively: apparently the IUPAC report and IUPAC project are completely reliable when you want to trumpet that the group 3 issue is a matter of convention, but unreliable on anything else, be it what it is actually suggesting, what Sc-Y-*-** actually does, or whether there is any actual convention in the literature at the moment. This does not make any sense. Pyykkö, who advocates Sc-Y-*-**, also thinks that these are length-15 "f-element rows". So who should we believe on a form Pyykkö likes, you or Pyykkö? Double sharp (talk) 17:16, 24 November 2022 (UTC)

Rare lawrencium., yes, never mind those four considerations. That most textbooks get it wrong is not an excuse for WP to propagate the error. Th is neither here nor there. Yes, it is a 5d element; yes there is a 5f presence in the crystalline form. Yes, neither Th nor Lr invalidate the argument that blocks start upon the appearance of the first relevant electron, nor the Scerri-Parsons global d/e anomaly argument. Yes, I look at textbooks and see that the traditional form is La-Ac. Yes I look at textbooks which get it wrong about At and I say that this not an excuse for WP to propagate the error. In the case of La or Lu in group 3 there is no primary error as such, only some controversy about which arrangement is the most appropriate. As the IUPAC group 3 project found, there is no objective way to adjudicate the matter. All of our arguments, as interesting as I have found them, and as much as I am still learning, seemingly amount to naught in the context of the IUPAC group 3 provisional report. No, I am not looking to turn a textbook disagreement into a convention; I am instead relying on WP policy including ENC, DUE, and NPOV.

Arguing against me. This is fine, and welcome. I only wish to note my arguments were found to be meritorious enough by the reviewers (one of whom was particularly formidable), including Scerri's oversight of my responses to the reviewers, to warrant publication. In contrast, you have unpublished and non-peer reviewed arguments, much as I find them interesting, to offer. Yes, you should write an article for FoC, as a contribution to the debate, as did Cotton who found (as you know) no case for changing from Sc-Y-La-Ac.

Only this time it's not Lavelle, it's you. As I set out in my article, it's (effectively) the entire chemistry establishment:


 * "In this context; the fact that nothing had changed with regard to the chemistry of lutetium; and that the physicists were content to leave the periodic table to the chemists, lanthanum kept its position under yttrium, and lutetium stayed at the end of the lanthanoids, never mind that the 4f subshell closed at ytterbium rather than lutetium."

Much as I have appreciated the perspectives of Jensen and Scerri on this matter, their opinions have been like sea flies dashing themselves upon the hull of the battleship of the chemistry establishment, going at full speed. Credit nevertheless for Scerri finding support within the organisational-politics-ridden IUPAC to commission the group 3 project.

Zinc. Thanks for the explanation about Zn. I see the same argument is used, happy to be corrected, to justify La as a 4f element (ligand donation) even though La is predominately a d valence element, as is Zn predominately an element (not a d element).

Scerri's opinion of Jensen. Scerri wrote the latter's arguments suffered from some limitations, including those related to electron configurations; physical and chemical properties; and evidence omitted from Christykaov's article (Scerri & Parsons 2018, p. 145).

By that logic, Lr must go under Tl, since it's the first p1. In fact this possibility had been considered, and dismissed, since it was already occupied by 113. Th is not consider special since it does not start a block.

Astatine. I talked about the chemistry of astatine in my 2013 article on which elements are metalloids:


 * "The chemistry of astatine is generally described as being similar to that of iodine, but with greater or “marked” metallic character.[64] There is some speculation that astatine in neutral aqueous solution has an oxidation state of +1;[65] it also apparently forms an At+ cation (as the aquo complex) in strongly acidic solutions.[66] Astatine is known to form what appears to be an At− anion in acidic or basic aqueous solutions in the presence of a moderately strong reducing agent;67 and metal astatides (analogous to metal polonides), have been prepared.[68] But it only takes a weak oxidizing agent to oxidize the At− anion (aq.) back to At (0).[69] Indeed, Thayer suggested that the most stable oxidation state of At appeared to be +1.[70] The foregoing description is however clouded by the extremely low concentrations at which astatine experiments have been conducted, and the possibility of reactions with impurities, walls and filters, or radioactivity by-products,[71] and other unwanted nano-scale interactions. Equally, as Kirby noted, “since the trace chemistry of I sometimes differs significantly from its own macroscopic chemistry, analogies drawn between At and I are likely to be questionable, at best.”[72]


 * Relativistic calculations predict that, with hydrogen, astatine will form a hydride rather than an astatide, that is, the positive charge is on the astatine atom.[73] Further, there are expected to be only three oxidation states within the limits of water stability: At(−I), At(I) and At(III), as At−, At+ and AtO+, respectively, in the range of pH 1−2. In more basic oxidizing solutions, AtO+ reacts with water to form AtO(OH), a species which appears to be dominant in these conditions.[74]


 * In brief, while astatine could reasonably be presumed to be a metalloid based on ordinary periodic trends, relativistic effects—as seen in gold, mercury, and the heavier p-block elements—are expected to result in condensed astatine being a ductile metal. Astatine could also be expected to show significant nonmetallic character, as is normally the case for metals in, or in the vicinity of, the p-block."

Aside from the pH stability range of At+ being extended to 7+, I see nothing to be concerned about At's status as a metal, bearing in mind I haven't read 2022 at length

In the context of Kirby it would seem there is nothing unusual about excluding At(OH)2+. That said, I will grant you there is a KMR between Sb and At, which GR-C does not mention.

Classifying At as a nonmetal would be the first ever case of an element expected to be a metal before it was discovered, and subsequently projected to have the electronic structure of metal, being classified as a nonmetal. An overturn-the-establishment outcome like that requires o-t-e evidence, which is not present. No, we don't have to throw out a whole bunch of textbooks, we just need to carefully note the differing perspectives, many of which, in the case of counting At as a nonmetal have evidently not done their homework.

IUPAC report. Yes, it says the Sc-Y-*-** form results in a 15-wide f block, which the report goes on to criticise on the basis that QM requires a 14-wide f-block, as was my point. OTOH, there is an electronic basis for a 15-wide f-block, as I have posted previously. Pyykkö is entitled to his opinion, which the IUPAC group 3 provisional report pooh-pooh'ed.

I feel that a simple consideration is that if a convention is needed on group 3, there already is one in that the most common form is Sc-Y-La-Ac.

I find it odd how the provisional report says nothing about that.

Funny how Reger, Scott and Ball (2010, p. 295) wrote...
 * "Perhaps the correct shape of the 32-column periodic table should feature a split d block given the electron configurations of La and Ac, but that "we avoid these structures by splitting the f block from the rest of the periodic table". This also has the advantage of being able to print a legible periodic table on a single piece of paper." (They show La below Y in the rest of their book.)

... and that provisional report makes no mention of this given it was included in our 2017 submission.

Funny how the provisional report is all over the 32-column form yet in their survey of 193 textbooks they found only five examples.

Evidently, it was objectively the "wrong" convention =8o

--- Sandbh (talk) 12:40, 25 November 2022 (UTC)

Please stop the distortions
Your arguments are based on a barrage of distortions, half-truths, and double standards adhered to despite careful correction based on reliable sources.
 * 1) You claim that Sc-Y-La-Ac is a "convention", when over half of the 2010s textbooks surveyed do not show it, and when the IUPAC project page explicitly says that there is enough variation in the literature to confuse students and instructors. It obviously cannot be a "convention" when a majority refuses to follow it.


 * When I refer to "a convention" I mean the most common form. For example:
 * "Solid/gas and solid/solid combustion synthesis in their conventional or most common form are conducted in very similar manners."
 * --- Kohse-Höinghaus K & Jeffries JB (eds) 2002, Applied Combustion Diagnostics, Taylor & Francis, New York, p. 588


 * As see in the accompanying image, according to the IUPAC Group 3 project survey of textbooks, the Sc-Y-La-Ac form is the most popular.


 * That the IUPAC project page says there is enough variation in the literature to confuse students and instructors is separate (albeit related) issue. Please do not conflate the two issues.


 * In this regard—as you kindly brought to my attention—Lars Öhrström, who was a member of the IUPAC Group 3 project, wrote in a publicly disclosed e-mail to Eric Scerri, chair of the Group 3 project:


 * "As you say, this is mostly a pedagogical issue. Students will always be annoyed when the answer is not 'yes' or 'no' but 'on one hand...' However there is value in learning that this is how things are in real life."


 * Sandbh (talk) 12:48, 27 November 2022 (UTC)
 * Per the Cambridge dictionary a convention is a way of doing something or appearing that is considered usual and correct. Something that the majority of authors flout is ipso facto not a convention. Double sharp (talk) 13:49, 27 November 2022 (UTC)
 * Please do not take the bait. Time. DePiep (talk) 08:15, 28 November 2022 (UTC)


 * 1) You claim that the valence-subshell argument for La and Ac belonging to the f-block is unpublished, when I have already pointed out that it is essentially an argument by Jensen (2015, he refers to the lack of "low-lying, readily accessible f-orbitals" for Lu). Not only that, but it also occurs in Hamilton (1965, as hydrogenic vs non-hydrogenic orbitals) and Wittig (1973). The point about transition elements having different electron configurations in different chemical contexts is so standard that it even appears in Feynman's lectures on physics. This is especially two-faced considering that you then turn around and apply this very valence-subshell argument to save Th for the f-block. Similarly, when it comes to La you insist that it must be under Y because it's the first occurrence of 5d, but you've just said that Nh can bump Lr to the 7p1 position despite coming later. Two-faced double standards again. This is even a more egregious double-standard because the argument you rely on, that only the first row of a block matters, does not occur in any of the literature besides your own text. Bohr did not think it was a requirement. Neither did Seaborg. Neither did most people before Seaborg; before him, most chemists didn't believe in an actinide series, so they obviously didn't think the lanthanide series had to be matched. Neither does anybody considering the g-block, because nobody delays it beyond 122, even though the first g-electron is supposed to occur only at 125. Neither does Lavelle, who refers to a pair out of place (despite the fact that his article was on your side). Neither do Reger, Scott, and Ball, who refer to Ac as well as La. You are pretending that your own understanding of chemistry is the consensus of sources when it simply isn't so. Even sources that agree with your conclusion do not agree with your reasoning. You are naturally free to publish original reasoning in your journal articles, but using them to justify what you want WP to do is basically the definition of WP:OR.


 * Thanks. What I claimed was that you have unpublished arguments. At no point did I say the valence-subshell argument for La and Ac belonging to the f-block is unpublished. My "only the first row of a block matters" argument about Th appears in my article. I have never implied that it appears anywhere else (I never looked specifically but it would not surprise me if it has been published before). Your contention that, "Neither does anybody considering the g-block, because nobody delays it beyond 122, even though the first g-electron is supposed to occur only at 125." is impossible to verify. I have never pretended that my own understanding of chemistry is the consensus of sources. I have however claimed that Sc-Y-La-Ac is the most common form, as you know, and as Scerri has noted. In this light, I have a view that the wp PT article should show the Sc-Y-La-Ac form. My peer-reviewed RS article supporting Sc-Y-La-Ac, consistent with Scerri's observation that Sc-Y-La-Ac is the most popular form, is one of many that goes into the mix of considerations. Sandbh (talk) 07:08, 28 November 2022 (UTC)


 * 1) You claim that textbooks may be superseded by the literature (and especially the original sources there) when it comes to calling astatine a metal, but you suddenly claim the opposite when it comes to moving La and Ac to the f-block (which the absolute majority of the literature on this subject demands, including the very first long-form table, which I mention since you have mentioned the 1940 discovery report for astatine). Considering just how many more papers there are supporting Sc-Y-Lu than Sc-Y-La, and Jensen's comment that in 1982 few chemists were aware of the dispute, it could equally justly be said that textbooks showing Sc-Y-La have not done their homework. Of course the sole bit of consistency here is that in each case the conclusion is the one you like: you think At is a metal but that group 3 should be Sc-Y-La, never mind that the arguments from the source situation for each are exactly contradictory.


 * Thanks. There is no controversy about astatine. I recall we had discussions at WP:ELEM several years back that resulted in the FAC astatine article, which I worked on with R8R, showing At as "probably metallic".


 * OTOH, there is a controversy about group 3. Furthermore, the provisional report from the IUPAC group 3 project found there was no objective way of adjudicating between the two options. So your studiously compiled list of sources, including my article, has no bearing on the issue. I recall I didn't have a view about At until I wrote my 2013 JChemEd article on "Which elements are metalloids" (50 citations) as spurned by the back and forth chaos at the wp metalloid article as to which elements were metalloids. Concurrently, Hermann et al. published their article, "Condensed astatine: Monatomic and metallic" in Physical Review Letters. At that time I had been speaking with Hawkes about the astatine situation, since he had argued that it was not a metalloid, as result of which he changed his mind and agreed it would be better counted as a metalloid. I asked Hermann about their paper to make sure that when they said At would be metallic, that they were not referring to At as a semimetal in the physics-based senses. He said no, At would be a full blown metal in the physics-based sense. Their prediction was consistent with Restrepo et al. who reported astatine appeared to share more in common with polonium (a metal) than it did with the established halogens. Ten years earlier Siekierski and Burgess (p. 122) had presumed the same thing i.e. metallic At. Hermann et al. have been cited 23 times, and about a decade has passed, and eighty years have passed since the eventual discoverers of At said they expected it would be a metal.


 * Re your statement:


 * "In each case the conclusion is the one you like: you think At is a metal but that group 3 should be Sc-Y-La, never mind that the arguments from the source situation for each are exactly contradictory."


 * I have explained the At situation. I thought it was better counted as a metalloid, as did Hawkes. Indeed, in my JChemEd article, I wrote: "Although the notion of astatine as a metal may seem odd, as it did to this author...".


 * I've changed my mind about the composition of group 3 on more than one occasion. While I wrote my FoC article in support of La, I subsequently changed my mind to Lu. In light of the Group 3 provisional report, I now support neither option. That said, if I was publishing a chemistry textbook I'd use the La form, as the most popular, and explain the relevance of *-** as the next most popular, and Lu as the least popular. Sandbh (talk) 11:35, 28 November 2022 (UTC)


 * 1) You claimed that Sc-Y-*-** did not have 15 elements in the f-block (The first arrangement emphasises similarities among the 15 Ln, making it "nonsensical" to refer to the 15 of them as f-block) in response to me pointing that together with Sc-Y-Lu-Lr it made a majority of textbooks considering lanthanum to be an f-block element (contra your viewpoint, naturally), when one of its leading proponents and the IUPAC project claims that it does. And in your very own article you claim that it does: The current confusion for students and teachers as to why the IUPAC table has a 15-element wide f-block... Of course, you then immediately changed your point above by claiming Yes, it says the Sc-Y-*-** form results in a 15-wide f block, which the report goes on to criticise on the basis that QM requires a 14-wide f-block, as was my point. How do you expect anyone to engage when you slipperily change your arguments midway and pretend you haven't?


 * Thanks. Yes, I claimed that Sc-Y-*-**, "emphasises similarities among the 15 Ln, making it "nonsensical" to refer to the 15 of them as f-block". That is to say, the f-block can (really) only be 14-wide.


 * In the Lu form, La is certainly shown as f-block. For Sc-Y-*-** one is obliged the check each individual textbook as to precisely which elements are designated as f-block. If memory serves I recall seeing at least one textbook in which only 14 of the Ln are counted as f-block, even though the reef at the foot of the table is 15-wide. Yes, the provisional report and I are in complete agreement as to the basically nonsensical notion of a 15-wide f block.


 * A further consideration is that when I looked up the taxonomical structure of periodic tables in 62 more recent chemistry textbooks, only 15% of them referred to block as such. See COPTIC results, preliminary.


 * In any event please do not conflate the Lu form (which is fine) with the nonsense of a *-** table showing all 15 Ln as f-block, and then claim that this means the majority show La as an f-element. Sandbh (talk) 12:28, 28 November 2022 (UTC)


 * 1) You continually twist sources out of context to support your agenda. You jump on the first bit of the IUPAC report calling the issue a "convention" and forget about all the rest of it where they suggest that Sc-Y-Lu-Lr be that convention. Then you refuse to believe what Scerri says he meant by the report, even though he wrote it. You jump on Ji et al. to claim 4f influence/involvement for Lu but fail to notice that they do not claim valence involvement, and that they say that that this involvement is weaker than that of the 5s/5p core electrons of Lu, which any chemistry sophomore knows are not valence electrons. You keep quoting Scerri and Parsons saying that Jensen has been selective, while failing to quote them saying that Jensen's arguments remain supportive of the Sc-Y-Lu table despite being inconclusive: they think the electronic arguments are "suggestive of the need to replace lanthanum with lutetium" and that Chistyakov's and Jensen's arguments "also support the replacement of lanthanum with lutetium but are also not conclusive", which in your selective quote has mysteriously gone missing. You quote Reger, Scott, and Ball p. 295 for saying that perhaps the table should have a split d-block, but neglect to inform us that right before that they said "Now that we know the underlying reason for the structure of the periodic table, we can argue that it should really have [no split d-block]", following Madelung. (And p. 301 shows that this is also a book that hasn't done its homework and thinks that astatine is a nonmetal.) And you attempted to conflate arguing against you with arguing against the referees who approved your article (please bear in mind you are arguing against me, the article peer reviewers, and Scerri as the editor-in-chief of FoC), which I exploded by pointing out that journals can and do publish opposing viewpoints. Finally, you explicitly refer to your imagination as to what you think the IUPAC project would've done if they had found Sc-Y-Lu to be the most popular form. And you hide behind Wikipedia policy seeking to start a poll, while already having demonstrated that you won't recognise a poll as obeying policy if it gives the result you don't like, e.g. at Talk:Periodic table.


 * Thanks. Yes, the opening paragraph of the provisional report of the group 3 project says:


 * "This situation makes it more important that IUPAC should make a ruling on the question which in the final analysis is one of convention rather than one that can be decided on objective scientific grounds."


 * No, they do not (as you put it): "suggest that Sc-Y-Lu-Lr be that convention." What they instead wrote was:


 * "Perhaps a compromise  could  be reached on the table...".


 * There is then a contradiction between what Eric wrote in the report, and what he later said in the lecture which was:


 * "We suggested that it should be option number two with lutetium and lawrencium."


 * So, where Eric reckoned "...it should be", the report that he wrote says, "could".


 * Yes, I cited Ji et al. to claim 4f influence/involvement for Lu and no more that that. Contrary to what you said I did, I made no reference to 4f valence orbital involvement.


 * Yes, wrt to Jensen, and in the second edition of his Red Book, Eric writes (pp. 394–396):


 * "Although the article by Jensen represents a major step toward reassignment of the elements lutetium and lawrencium to group 3, the proposal suffers from some limitations that have resulted in its not having the impact that it might have had."


 * "It appears that Jensen did not take the trouble to investigate precisely when the assignment had first been proposed since it was a matter of about 50 years rather than 'more recent spectroscopic work.'"


 * "The second limitation is that Jensen has been too selective in the evidence he puts forward to support his case (figure 13.10). If other forms of data are appealed to, the case becomes somewhat less compelling."


 * "It should also be mentioned that Jensen was not responsible for assembling this particular data or for presenting it in the fashion shown in his article. As Jensen acknowledges, he was using the data collected and plotted some years earlier by V. M. Christyakov, whose data is somewhat more comprehensive than what Jensen chose to display in his 1982 article."


 * "The data for group 3 metals in figure 13.11 is presented in two ways: first with lanthanum and second with lutetium in place of lanthanum. Lanthanum seems to conform to the general downward trend better than lutetium, contrary to Jensen's proposal, thus further underlining the inconclusive nature of arguments based on specific chemical and physical data."


 * Indeed, as Scerri & Parsons (2018) added (p. 143):


 * "It would seem that this article has not convinced many authors since the majority^ of periodic tables have remained unchanged and the debate has continued."


 * ^ 65% of books published from 1985 to 2018, as recorded in the IUPAC survey show Sc-Y-La-Lu.


 * No, I have not referred to Scerri & Parsons writing that Jensen was selective. Instead, what I wrote was:


 * "Scerri's opinion of Jensen. Scerri wrote the latter's arguments suffered from some limitations, including those related to electron configurations; physical and chemical properties; and evidence omitted from Christykaov's article (Scerri & Parsons 2018, p. 145)."


 * Please do not conflate your erroneous impressions of what I wrote with what I actually wrote.


 * Regarding:


 * "You quote Reger, Scott, and Ball p. 295 for saying that perhaps the table should have a split d-block, but neglect to inform us that right before that they said "Now that we know the underlying reason for the structure of the periodic table, we can argue that it should really have [no split d-block]".


 * Yes, I omitted that as it wasn't relevant given what they write immediately thereafter:


 * "According to the aufbau principle, in the sixth and seventh periods, the f block comes before the d block, therefore, those elements should be positioned right next to the s block in those periods. However, if we look closely at the electron configurations of the elements right after the s block elements barium and radium, we find that the next electron goes into a d subshell, not an f subshell. The electron configuration of lanthanum is [Xe]6s2 5d1 (rather than [Xe]6s2 4f1), and the electron configuration of actinium is (Rn]7s26d1 (rather than [Rn]7s2 5f1). Therefore, perhaps the correct shape of the periodic table should be...


 * Now we have a periodic table with a split d block. We avoid these structures by splitting the f block off from the rest of the periodic table. This also has the advantage of being able to print a legible periodic table on a single page of paper.


 * Yes, they (2010) show At as a nonmetal. No surprise since we know from lists of metalloids that At appeared as a metalloid about 40% of time up to 2008.


 * Yes, I wrote, "please bear in mind you are arguing against me, the article peer reviewers, and Scerri as the editor-in-chief of FoC". No, you did note explode anything by pointing out that journals can and do publish opposing viewpoints. Of course they do. So what? Publication of an article in a reputable journal indicates the author has crafted a thesis judged worthy by peer reviewers and the journal editor of being added to the literature. In contrast, your arguments (AFAIK) have been confined to Wikipedia, which is not regarded (in academia) as a RS.


 * Yes, I explicitly referred to my imagination as to what I thought the IUPAC project would've done if they had found Sc-Y-Lu to be the most popular form.


 * No, I do not:


 * "...hide behind Wikipedia policy seeking to start a poll, while already having demonstrated that you won't recognise a poll as obeying policy if it gives the result you don't like, e.g. at Talk:Periodic table#To poll or not to poll; that is the question."


 * Firstly, I did not revisit the question as to which PT should be shown in the lede of the PT article; that was initiated by another editor. Secondly I was not able to take part in the poll that resulted in the adoption of the Lu form. Finally, and yes, in my view the poll outcome was and is inconsistent with WP policy including WP:ENC, WP:NPOV, and WP:DUE. Sandbh (talk) 11:58, 30 November 2022 (UTC)

I'm not interested in discussing with you if you're going to base your case on distortions and half-truths and your own imagination of what the IUPAC project might have done: I can just imagine the whoopin' and hollerin' and front page treatment, if the Lu form had been found to be the most popular). Actually, the IUPAC project was not formed for the reason you wrote; it was rather formed via lobbying efforts by Scerri. And another excellent exemplar, incidentally: you call it "lobbying efforts", never mind that per IUPAC itself one is supposed to send a project submission form to them before a project is formed. As usual, the IUPAC project is painted in the worst possible light with fear, uncertainty, and doubt. The one constant behind all your twisting and turning is an attempt to shore up the La form that you wrote a long article in favour of. This is the very definition of POV-pushing: note the clause "including on talk page discussions". Stop wasting my time. Double sharp (talk) 21:41, 26 November 2022 (UTC)

For your attention, because you have contributed to this thread, as well as its progenitor at Talk:Periodic table. Double sharp (talk) 21:58, 26 November 2022 (UTC)


 * I understand that the policy re POV-pushing "including on talk page discussions" applies to article talk pages rather than to user talk pages. I note this thread was started by you and I have subsequently responded to your perspectives with my opinions, explanations, corrections and citations.


 * Since you have posted to my talk page…


 * "Your arguments are based on a barrage of distortions, half-truths, and double standards adhered to despite careful correction based on reliable sources”


 * …I’ll address these concerns by posting directly after each of your paragraphs. 118.211.127.42 (talk) 11:06, 27 November 2022 (UTC)
 * ...and by doing so obfuscating the paragraph numbers, which I then had to fix. Double sharp (talk) 21:28, 27 November 2022 (UTC)
 * Thanks for that; I had no intention of obfuscating the paragraph numbers. Sandbh (talk) 12:41, 30 November 2022 (UTC)


 * Re lobbying: In the case of group 3, we know that IUPAC had a dim view of doing anything about this from the August 2013 minutes posted by FJ, in Group 3 talk: IUPAC committee decides that the organization of the periodic table isn't their business. So, yes in such an environment, one "lobbies" for support and one then puts the proposal in. That is Organisational Politics 101.


 * Re: "...the IUPAC project is painted in the worst possible light with fear, uncertainty, and doubt." No, I quote from what the report says. Yes, we know from Scerri's public lecture that another member of the project appears to see things differently from how the chair of the report sees it. Yes, we know from the same lecture that Eric Scerri is concerned that IUPAC seems like it will not do anything with the report.


 * Yes I wrote an article published in Foundations of Chemistry in support of the La form, although this is no longer my position. As I wrote previously, I understand POV-pushing applies to article talk pages. This is not an article talk page. Further, as noted, this thread was started by you and I have subsequently responded to your perspectives with my opinions, explanations, corrections and citations. Sandbh (talk) 12:41, 30 November 2022 (UTC)


 * for all intents purposes, above Doube sharp has concluded the discussions by meta-response, and so there is no need or ground to restart individual arguments. If Sandbh wishes to nitpick isolated points, they better do so elsewhere. Anyway, I will not accept any effects of such rabbithole distortions from here as "argumentation" in talkspace, nor in mainspace. Also, reproducing proven distortions elsewhere could be treated as unacceptable behaviour. Double sharp: do not take the bait.

Thanks for posting your opinion. Sandbh (talk) 12:41, 30 November 2022 (UTC)

Please stop the distortions: DePiep thoughts
Thanks, Double sharp, for posting this. Very well-written and well-based. Describing the extended developments (in talk & articles, in long posts, in repeated and/or disformed or deviated threads). I can recognise & support the spot researches by Ds, albeit that the straight elconfig arguments [#2] are beyond me&mdash;but not excluding the agendised source-utilisations thoughout. I could add my number #6, partly overlapping with #1-5 but a reappearing misargumentation in-pattern IMO.
 * # 6 [by DePiep]: You, Sandbh, are using the presentation form 32- or 18-column periodic table by itself as a scientific statement about group 3. That is: tallying authors (who might not have done their homework, whose publication might not have been about group 3 consitution at all, who might have published before IUPAC(2021) because after all the IUPAC team's research was initiated because of new reseach information, and who did not do new reseach at all for their textbook ie not a research paper, and of course who a priori have not intended to choose between 18- or 32-form as a statement), that tallying is not an acceptable RS base. For example: Funny how the provisional report is all over the 32-column form yet in their survey of 193 textbooks they found only five examples ( 25Nov 12:40 above). I note that IUPAC(2021) distinguishes between "Sc-Y-blank-blank" (specialistic, QM, 3rd form) and "Sc-Y-*-*" [ie, allLAN-allACT in group 3, and a 15-column wide Sc and Y cells]: rejected full stop, also an indicator of non-researched 'statement'.

So, thank you Double sharp. DePiep (talk) 08:13, 27 November 2022 (UTC)


 * The IUAPC provisional report uses the presentation form 32- or 18-column as a consideration about group 3. The authors I tallied were tallied by the IUPAC group 3 project itself (look under the Progress tab). The provisional report distinguishes between Sc-Y-La-Ac; Sc-Y-Lu-Lr; and the IUPAC form. For the IUPAC form the report says:


 * "The periodic table that is sometimes labeled as “IUPAC periodic table” as shown in figure 3 avoids assigning the 3rd and 4th members of group 3 altogether, by simply leaving empty spaces below Sc and Y."


 * This is wrong. In the two boxes under Y the IUPAC form shows "57-71 lanthanoids" and "89-103 actinoids".


 * Nowhere in the IUPAC provisional report do they distinguish between "Sc-Y-blank-blank" and "Sc-Y-*-*". The two abbreviations refer to the same table i.e. the IUPAC form.
 * --- Sandbh (talk) 12:03, 27 November 2022 (UTC)
 * You are distorting again by calling Sc-Y-*-** / Sc-Y-blank-blank "the IUPAC form". In the 2021 report it is specifically noted that As Jeffrey Leigh reminded readers of this magazine not long ago, IUPAC does not officially support any particular form of the periodic table even though the organization frequently publishes a period table with the label of “IUPAC periodic table”. And later this form is only called The periodic table that is sometimes labeled as “IUPAC periodic table”, as you quote. You are leaving out important context by unreservedly calling it "the IUPAC form". Double sharp (talk) 13:38, 27 November 2022 (UTC)


 * Thank you. I call it the IUPAC form out of convenience. Even IUPAC label it the "IUPAC Periodic Table of the Elements". As we both know, of course, there is no such thing as an IUPAC endorsed PT per se. Sandbh (talk) 07:02, 1 December 2022 (UTC)


 * Sandbh: IUPAC .. uses the presentation .. consideration: disingeneous representation of the source. (A better key word to start from is "mask"). As for I did not tally, IUPAC did: they did not draw scientific conclusions from it. While you do, being scientifically disingenious. Even simple & better: the link you provided yourself states that IUPAC will not choose preference between graphic 18 or 32&mdash;already in 2015. the IUPAC form shows .. There is no "the IUPAC form". This is not your sloppyness any more, this is scientific duplicity. Nowhere in the IUPAC provisional report ..: yes there is. There is no 14 or 15-wide Sc, Y tablecell; and OTOH it explicitly says "empty".
 * All statements by Double sharp (and I understand, mine too) still stand. Not a dent. Instead, you confirming the duplicity the thread #1–#5 (–#6?) is about. DePiep (talk) 16:14, 27 November 2022 (UTC)


 * Thank you DePiep. There is no high "scientific" conclusion to be drawn from the survey of textbooks, as published by the IUPC group 3 project; what is thing there only amounts to some basic arithmetic. Scerri has already acknowledged that the La form is in the majority; see the second edition of his red book p. 377; and again at p. 394. The textbook survey backs him up. IUPAC itself has acknowledged there is no IUPAC endorsed form. You are right; IUPAC will not choose between the 18 or 32-column form. The provisional report nevertheless refers to 32-column PTs. Yes, what I said is accurate: "Nowhere in the IUPAC provisional report do they distinguish between "Sc-Y-blank-blank" and "Sc-Y-*-*"." The two forms are identical i.e. two blank spaces under Y are equivalent to *-** under Y. Sandbh (talk) 07:02, 1 December 2022 (UTC)

(1) The POVPUSH sentence is: The term "POV-pushing" is primarily used in regard to the presentation of a particular point of view in an article, including on talk page discussions. So: not "only" just "primarily", and not limited to article-talkpages as partial quote suggest (also, q.e.d. wrt selective quoting).

(2) re: by posting directly after each of your paragraphs. one is free to do so I guess, though it is not a way to disprove the meta statement.

(3) in general, let me quote Double sharp: Stop wasting my time. More specific: you are near the limit of acceptable stubbornness. Draining editor's energy is one step, frustrating the encyclopedia is one step too far. DePiep (talk) 11:28, 27 November 2022 (UTC)


 * (1) : I understand I can express my POV on my talk page. If you do not agree you are welcome to say so or to ignore my POV. If you post to my talk page I will usually respond.
 * (2) Noted.
 * (3) All editors are welcome to post at my talk page. If you disagree with my views you are welcome to say so. If you feel you would be wasting your time by doing so, that is fine to. Sandbh (talk) 12:03, 27 November 2022 (UTC)


 * Sigh. One more try:
 * re I can express my POV on my talk page Who was challenging that?
 * re I can express my POV on my talk page Go ahead. But your POVs don't matter. What matters is that you do not understand they are not encyclopedic statements fit for article.
 * You are evading the essence. Whether intentionally or unconsciously: irrelevant. DePiep (talk) 15:51, 27 November 2022 (UTC)


 * : Thank you DePiep. Me expressing my POV on my talk page was challenged when you wrote just above:
 * "So: not "only" just "primarily", and not limited to article-talkpages as partial quote suggest (also, q.e.d. wrt selective quoting)."
 * Yes, encyclopedic content must ultimately be traceable to RS and be consistent with e.g. WP:ENC, WP: NPOV; and WP:DUE.


 * I consider this discussion closed. in  above, gives a meta-overview of the discussion(s) and what went wrong (of course, other talks are involved). The meta analysis covers content issues (like RS-handling, -quoting, -arguing, answering questions), and methodologic issues (thread-organising, -forking, -flow, non-answer-building, deviating, attacking consensus-building). Altogether, aptly titled distortions.


 * Being a closed thread & topic, I will not reengage in replies. At all. I am free to ignore them. As Double sharp wrote: Stop wasting my time.


 * If you consider reopening this topic, in any place or time or sense, it is up to you to start with a sincere clarification on why it would be different this time. This says that without reflection on the whole, including & especially on your own input & behaviour, a new talk will not likely be met with the type of attention you expect. To spell it out: _nothing_ I say is a suggestion of some edit limitation (duh), _all_ I say is a warning that your edits will be met with extra critical checks following this expensive story.
 * User:DePiep 11:47, 1 December 2022 (UTC) [late signing, reping needed: 13:32, 1 December 2022 (UTC) ]


 * Thank you for you opinion and advice. If you post to my talk page, as you are welcome to do, I reserve the right to respond. Sandbh (talk) 00:29, 2 December 2022 (UTC)


 * these edits in Naming conventions (chemistry) (a MOS no less) I now consider disruptive editing. I think level3 is applicable:
 * Nuvola apps important.svg Please stop your disruptive editing.

If you continue to disrupt Wikipedia, you may be blocked from editing.
 * If you are engaged in an article content dispute with another editor, discuss the matter with the editor at their talk page, or the article's talk page, and seek consensus with them. Alternatively you can read Wikipedia's dispute resolution page, and ask for independent help at one of the relevant noticeboards.
 * If you are engaged in any other form of dispute that is not covered on the dispute resolution page, seek assistance at Wikipedia's Administrators' noticeboard/Incidents.
 * -DePiep (talk) 13:40, 1 December 2022 (UTC)


 * . Thank you. I do not consider my reversions to be disruptive edits in accordance with the reasons I gave for the reversions namely that the content involved has nothing to do with naming conventions, noting that the name of the article is Naming conventions (chemistry). In this regard I am following normal wp protocol and conventions, including WP:BRD. Sandbh (talk) 00:23, 2 December 2022 (UTC)


 * . I believe I have responded to all of your posts to my talk page. If I have missed anything and you are interested in a response please ping. Thank you. Sandbh (talk) 00:32, 2 December 2022 (UTC)
 * I replied at . That reply includes re the wording "naming convention". And yes, you are the master of your own talkpage, & I neither do nor did take anything away from that. Even better, I clarified by F3-able wording _nothing_ and _all_.
 * While researching that reply just now (specifically, our abandoning of element classification coloring), my eye fell upon this archived note by . I did not follow or use the link, but I do point out the actual link title (which, of course, is why I noticed it while not looking for it). -DePiep (talk) 09:09, 2 December 2022 (UTC)

Even more blatant examples of distortion
One absolutely blatant example I forgot to add: when it comes to disputing the composition of group 3, Sandbh casts Sc-Y-La as "the chemistry battleship" (never mind that it has less than a majority), and say that Scerri's and Jensen's opinions have been like sea flies dashing themselves upon the hull of the battleship of the chemistry establishment, going at full speed. (Comparing opinions to insects: not exactly balanced or polite, I might add.) But what about when it comes to whether yttrium is more similar to light lanthanides (that includes La) or heavy lanthanides (that includes Lu)? The chemistry establishment all agrees Y is closer to the heavy lanthanides: But of course, on the grounds of just one dissenting source (Restrepo), Sandbh decides to pooh-pooh all of that: Re "Y fits perfectly in the late lanthanide series" I tend to doubt this. Recall Restrepo found that in stoichiometric terms, La fitted best with Y rather than Lu.
 * Greenwood and Earnshaw, 2nd ed., p. 1234: By the time Ho is reached the LnIII radius has been sufficiently reduced to be almost identical with that of YIII which is why this much lighter element is invariably associated with the heavier lanthanides.
 * Cotton, Lanthanide and Actinide Chemistry, p. 107: By the end of this chapter you should be able to: recognize that yttrium resembles the later lanthanides in its chemistry
 * Old-school classic separation procedures, in which Sc, Y, and Lu were considered yttrium group elements, whereas La and Ac were considered cerium group elements.

This is the most obvious evidence yet that Sandbh is uninterested in what the consensus of reliable sources actually is, and is actually selectively using and twisting them to support his own opinions. In 2021, he thinks Sc-Y-Lu is OK, so when somebody asks about the group 3 problem on the talk page, it ends without any fuss. In 2022, he thinks Sc-Y-Lu is not OK, so he wastes everybody's time for a month, and refuses to recognise a unanimous consensus. And it really seems to be about what he is convinced by in particular. To quote from Talk:Periodic table:

"DS: 'P.S. You didn't seem to mind it being Sc-Y-Lu-Lr when somebody asked about it on this talk page last year.' :) Double sharp (talk) 09:37, 16 October 2022 (UTC)

Your archive fu is impressive.

Yes, I’m equivocal about the group 3 question but strive to be principled about what WP, as an encyclopaedia, should show. Sandbh (talk) 10:52, 18 October 2022 (UTC)

Yet last year you used your own OR argument to support Sc-Y-Lu on the talk page. Double sharp (talk) 15:37, 30 October 2022 (UTC)

@Double sharp: Yes; thanks for the reminder. At that time it was an impressive argument based on a rubric that only applies to the f-block. As we have discussed, the other argument concerns the electron configurations in the trivalent cations, where regularity is better with group 3 as Sc-Y-La-Ac. Further, as Wulfsberg has observed, the configurations of the ions are more important than the gas phase configurations. Sandbh (talk) 23:29, 7 November 2022 (UTC)

@Sandbh: But the point is that that argument was OR, which seems inconsistent with being, as you say, 'principled about what WP, as an encyclopaedia, should show'. We clearly disagree about what is most appropriate to show on WP, but surely we should be arguing based on sources? ... Double sharp (talk) 23:49, 7 November 2022 (UTC)

@Double sharp: Thanks. Yes, my argument was OR, which I understand we are able to engage in on a talk page; as OR it didn't make it into the article space. Actually, on the OR question, it's no more than simple fact-based arithmetic so there's an argument it would be OK somewhere in article space. ... Sandbh (talk) 01:33, 8 November 2022 (UTC)

@Sandbh: It is more than simple fact-based arithmetic. You are referring to oxidation numbers, but you then quote configurations of ions with that number as a charge. The very article you link to says that oxidation number and charge are not the same thing and that for that reason, oxidation states are sometimes called formal oxidation states: Hence, the oft-encountered term, formal oxidation state, and OS is often represented using Roman numerals (I, II, III etc.) to distinguish it from a real charge for which Arabic numerals (1, 2, 3 etc.) are employed. So it is not just WP:CALC: you are taking an extra step that requires RS support and, worse, seems to directly contradict the RS you are using to support it.

The talk page is meant as a forum aimed at article improvement, not airing personal views. Articles must be based on RS, so OR cannot be used to improve the article. This discussion is even precisely exemplifying why not by showing OR in contradiction with the RS used to back it up. Therefore, there doesn't seem to be any point to discussing it on the talk page. ... Double sharp (talk) 09:55, 8 November 2022 (UTC)"

The one constant seems to be: if Sandbh agrees with what is being shown, there won't be any big walls of text posted; but if he doesn't, not even a unanimous consensus will dissuade him from wasting everyone's time.

P.S. Whether or not to call metalloids nonmetals is another good example. Yes, a few advanced monographs (e.g. Steudel) do this. Most textbooks don't. But of course, Sandbh thinks metalloids should be nonmetals, so that appears throughout Nonmetal. And he even cites himself for it in that article. At other times they are counted as nonmetals in light of their nonmetallic chemistry, and who do we find cited but "Vernon 2020". A bit later we fnid Chemically the metalloids generally behave like (weak) nonmetals. Among the nonmetallic elements they tend to have the lowest ionization energies, electron affinities, and electronegativity values, and are relatively weak oxidizing agents. They further demonstrate a tendency to form alloys with metals., and again who do we find but "Vernon 2013". For goodness' sake. I regret supporting the FAC last time, should've researched the textbooks some more. Double sharp (talk) 21:23, 27 November 2022 (UTC)


 * re part 1: yes, more examples of bad reasoning & source distortion, including chaotic talk, thread & response building. re part 2: article nonmetal is a separate issue (with recurring pattern sure), to be handled elsewhere.
 * I consider this year's Group 3 discussion concluded, productively resulting in current MOS:PERIODICTABLE. I wont expand the discussion by itself, but any effects spoiling (into) mainspace will be checked. DePiep (talk) 08:02, 28 November 2022 (UTC)


 * Thank you for your conclusion and for alerting me to MOS:PERIODICTABLE. Sandbh (talk) 12:04, 1 December 2022 (UTC)


 * Thank you.


 * Yes, since it was realised in 1937 that the 4f shell closed at Yb rather than Lu, and that nothing changed with regard to the chemistry of lutetium, and that the physicists were content to leave the periodic table to the chemists, lanthanum kept its position under yttrium, and lutetium stayed at the end of the lanthanoids.


 * In 1982, Jensen published his article in the Journal of Chemical Education re-examining the composition of Group 3 and asserting that lutetium should be under yttrium, rather than lanthanum.


 * What happened? Effectively nothing.


 * As Scerri & Parsons (2018) wrote (p. 143):


 * "It would seem that this article has not convinced many authors since the majority of periodic tables have remained unchanged and the debate has continued."


 * ^ 65% of books published from 1985 to 2018, as recorded in the IUPAC survey show Sc-Y-La-Lu.


 * So yes, the battleship of the chemistry establishment has plowed on, unperturbed and, judging by Lars Öhrström's email, will continue to do so.


 * Turning now to yttrium.


 * In terms of chemical separation behaviour, that scandium, yttrium and lutetium occurred in the so-called yttrium group, and that lanthanum occurred in the “cerium” group did not imply anything particularly significant; it is simply a reflection of the increasing basicity of these elements as atomic radius increases. Taking the alkaline earth metals as another example, magnesium (less basic) belongs in the "soluble group" and calcium, strontium and barium (more basic) occur in the "ammonium carbonate group". Moving lutetium under yttrium because they occur in the same chemical separation group failed to consider separation group patterns elsewhere in the periodic table.


 * Further, the separation group behaviour of yttrium can be ambiguous, and scandium, yttrium, and lanthanum appear to show complexation behaviour different to that of lutetium. As observed by Vickery (1960, p. 37):


 * "In separating yttrium from the heavy lanthanoids, advantage is always taken of the phenomenon by which yttrium sometimes assumes characteristics similar to those of the light lanthanoids, and sometimes follows the heavy lanthanoids in behaviour."


 * Over a decade later Vickery (1973, p. 344) observed that:


 * "Polymerization of the yttrium ion has been shown now to account for its apparently nomadic behaviour in earlier classical separation techniques. Evidence is also available for the existence of lanthanum hydroxy-polymers in solution. There is, indeed, to be seen an interesting sequence through…Group III in this respect. Hydroxyl bridged polymerization has been shown for aluminium, scandium, yttrium, and lanthanum ions, but does not appear to exist with the series Ce3+ → Lu3+. On the other hand, gallium, indium and thallium do appear to complex in this fashion. On a thermodynamic basis, ionic hydration—or hydroxo complex formation—may depend upon free energy rather than enthalpy and plots of such free energy link the pre-lanthanon triad more closely to aluminium, on the one hand, and gallium, etc., on the other, than to the lanthanoid group of elements."


 * Moreover we can look at periodic trends in chemical reactivity, as observed in the reactions of Sc+, Y+, La+ and Lu+ with H2, D2, HD, CH4, and C2H6 (Elkind et al. 1989; Sunderlin and Armentrout (1989).


 * The first ionization energy of the elements, as a first order approximation, is a useful indicator of periodic trends. That is why the monocations of these metals, while not being representative of their general (trivalent) chemistry, can nevertheless shed some light on their interrelationships. Hydrogen represents one of the two elements, the combining power of which Mendeleev based his periodic table of elements on, the other element being oxygen.


 * Under the experimental conditions set out in the articles, the Lu+ system was found to be rather different from the other three systems in several respects, including electron configuration, reactivity onset, thermodynamic behaviour, and interactivity mechanism. Meanwhile, scandium, yttrium, and lanthanum showed properties consistent with periodic trends. The different behaviour of lutetium has been attributed to an indirect effect of its 4f14 subshell.


 * Bear in mind that the Y considerations I’ve listed above are but one argument pointing to La under Y.


 * As far as the observations of Greenwood & Earnshaw, and Cotton go, which I don’t dispute, it is evident that these have had no influence on the debate given the lack of any movement on the composition of group 3 since 1937. Indeed, G&E show group 3 as Sc-Y-La-Ac; as does Wiberg; as does Cotton & Wilkinson. I further note Cotton et al.’s recent article finding no support for a change from Sc-Y-La-Ac to Sc-Y-Lu-Lr on structural chemistry grounds.


 * The key consideration is that similarity in behaviour between Y and Lu does not necessarily connote a group relationship. We said as much in our 2017 submission to IUPAC:


 * "In advancing their positions, we think these authors fail to demonstrate why similarity in properties (aside from valency) necessarily connotes group membership. In some other parts of the periodic table, most germanely in groups 1 and 2, we see a continuation of trends upon descending a group (such as increasing atomic radius, basicity and electropositivity), rather than a convergence of such properties. Either pattern could apply to the eka-yttrium position. That is to say, if group 3 were treated as early main group elements we would expect more of a linear trend going down the group. On the other hand, if group 3 was treated as a transition metal group, it would be reasonable to expect more of a convergence of properties on going from period 5 to period 6, as a result of the lanthanide contraction."


 * Cotton and team in their 2022 came to the same conclusion:


 * "Whilst in many of these comparative series lutetium resembles scandium in its behaviour, there are more cases where lutetium resembles yttrium. So, in the discussion of whether the order of the elements for Group 3 should be Sc, Y and La, or whether Lu should replace La in the group, this detailed review of the structural chemistry indicates that there is a logical progression in chemistry as the size of the Sc, Y and La ions increase. The structural chemistry of Lu most closely matches that of Y and not of La, so we feel that the case for replacing La by Lu in Group 3 has not been made on structural grounds. In the absence of more compelling evidence, the Periodic Table as presented currently, not least in the IUPAC form, gives the most appropriate description of the chemistry of Group 3 and of the lanthanides."


 * So no, I was not relying on the grounds of one dissenting source.


 * Quoting me is fine and if you do so please do not quote me out of context. Here is the rest of that thread:


 * Thanks for the ping. Yes, oxidation numbers and charge numbers of ions are interchangeable in the literature, at the first order level. This is what Simon Cotton does when he gives the electron configurations and oxidation numbers of Ln+3 and An+3 cations. Yes, it is sometimes useful, to distinguish between the two, at a higher order of modelling, in order to further appreciate the fine nuances of a situation, as I acknowledged, and as that source I cited does. None of this is a personal view; it is what occurs in the literature. I mentioned the two other sources, in passing, out of incidental courtesy, since the topic of the thread was oxidation numbers. Sandbh (talk) 06:57, 10 November 2022 (UTC)
 * I agree that this is the case to a first order level, as you say. However, it is not clear to me that it is being used at that first order level when it is brought into the group 3 dispute. You've mentioned Wulfsberg, who indeed says that "ions are more important than isolated gaseous atoms for nearly all atoms". But in the very same paragraph he supports Sc-Y-Lu-Lr as group 3. Or you can look at Jørgensen (p. 228), who has said that Madelung anomalies are irrelevant and points to the fact that nearly all the anomalies disappear in cations M2+ through M6+ (so once again he's looking at ions rather than gaseous atoms). But he also thought that Lu is most conveniently considered as the first 5d element. That seems to indicate to me that it's not obvious or generally accepted that it's enough to stop at the first-order "La3+ 4f0" idea. Because as you've noted, stopping at the first order would seem to naturally support Sc-Y-La-Ac, but they mention it and then support Sc-Y-Lu-Lr anyway. That cannot involve stopping at the first order.
 * As I mentioned, your sources are appreciated. That said, I'd like to request that such links that are not quite relevant to an ongoing conversation are put on my user talk page in future. Not only does that keep the conversation more on-topic, but it also helps me to find those sources later when I need them. :) Double sharp (talk) 16:11, 10 November 2022 (UTC)
 * Thanks. We noted in our joint 2017 submission to the IUPAC group 3 project the inexplicable discrepancy between what Wulfsberg said on the one hand about the importance of ions, and on the other hand, his depiction of group 3. Wulfsberg cites Cherkesov (1984); Jensen (1982); Chistyakov (1968); Merz & Ulmer (1967); and Hamilton (1965). Jensen's article was criticised by Scerri as being selective. Chistyakov was subject to criticism from Scerri for only looking at the second IE. We too criticised Chistyakov for only comparing Sc-Y-Lu to the trends in groups 4-8 and ignoring what was happening in groups 1−2. Merz and Ulmer were contradicted by Bergwall (1966). Hamilton (inconclusively) said, "There are at least several intermetallic compounds where the compound with La has a different crystal structure from the corresponding compounds with Sc, Y, and Lu." This is not entirely unexpected. Given its position in the next row down in the periodic table, lanthanum atoms are larger than scandium or yttrium atoms. It would therefore stand to reason that they should not be able to pack in a crystal structure in quite the same way as the smaller scandium, yttrium, or lutetium atoms. He also relied on excited state spectra, completely overlooking what happens in group 2, with Ca-Sr-Ba.
 * Thanks. We noted in our joint 2017 submission to the IUPAC group 3 project the inexplicable discrepancy between what Wulfsberg said on the one hand about the importance of ions, and on the other hand, his depiction of group 3. Wulfsberg cites Cherkesov (1984); Jensen (1982); Chistyakov (1968); Merz & Ulmer (1967); and Hamilton (1965). Jensen's article was criticised by Scerri as being selective. Chistyakov was subject to criticism from Scerri for only looking at the second IE. We too criticised Chistyakov for only comparing Sc-Y-Lu to the trends in groups 4-8 and ignoring what was happening in groups 1−2. Merz and Ulmer were contradicted by Bergwall (1966). Hamilton (inconclusively) said, "There are at least several intermetallic compounds where the compound with La has a different crystal structure from the corresponding compounds with Sc, Y, and Lu." This is not entirely unexpected. Given its position in the next row down in the periodic table, lanthanum atoms are larger than scandium or yttrium atoms. It would therefore stand to reason that they should not be able to pack in a crystal structure in quite the same way as the smaller scandium, yttrium, or lutetium atoms. He also relied on excited state spectra, completely overlooking what happens in group 2, with Ca-Sr-Ba.
 * Thanks. We noted in our joint 2017 submission to the IUPAC group 3 project the inexplicable discrepancy between what Wulfsberg said on the one hand about the importance of ions, and on the other hand, his depiction of group 3. Wulfsberg cites Cherkesov (1984); Jensen (1982); Chistyakov (1968); Merz & Ulmer (1967); and Hamilton (1965). Jensen's article was criticised by Scerri as being selective. Chistyakov was subject to criticism from Scerri for only looking at the second IE. We too criticised Chistyakov for only comparing Sc-Y-Lu to the trends in groups 4-8 and ignoring what was happening in groups 1−2. Merz and Ulmer were contradicted by Bergwall (1966). Hamilton (inconclusively) said, "There are at least several intermetallic compounds where the compound with La has a different crystal structure from the corresponding compounds with Sc, Y, and Lu." This is not entirely unexpected. Given its position in the next row down in the periodic table, lanthanum atoms are larger than scandium or yttrium atoms. It would therefore stand to reason that they should not be able to pack in a crystal structure in quite the same way as the smaller scandium, yttrium, or lutetium atoms. He also relied on excited state spectra, completely overlooking what happens in group 2, with Ca-Sr-Ba.


 * Of course, Chistyakov; Merz & Ulmer; and Hamilton were cited by Jensen, so why Wulfsberg felt the need to recite them is inexplicable.


 * The only new citation Wulfsberg gave was Cherkesov (1984), who says that Al-Sc-Y-Lu and Lr are close analogues, but so too are Y-La-Ac. He concludes by saying there is no reason why Lu-Lr could not go under Sc. I'll ping you a copy of this article for your assessment.


 * Jørgensen neither provides a PT showing the composition of group 3 nor any grounds, that I could find, for saying Lu can most conveniently be considered as the first member of the 5d series. Sandbh (talk) 07:20, 13 November 2022 (UTC)
 * I'll respond at your talk page. Double sharp (talk) 13:41, 13 November 2022 (UTC)
 * I'll respond at your talk page. Double sharp (talk) 13:41, 13 November 2022 (UTC)


 * IOW you've arrived back where you started from, on this talk page.


 * Yes, there was a unanimous poll outcome. I have not disputed that. IMO, however, the outcome of that nigh on two year old poll is not consistent with WP:ENC, WP:NPOV; and WP:DUE.


 * I'll respond in a new section to your concerns about metalloids etc. Sandbh (talk) 12:04, 1 December 2022 (UTC)

Metalloids
Earlier you posted:


 * "P.S. Whether or not to call metalloids nonmetals is another good example. Yes, a few advanced monographs (e.g. Steudel) do this. Most textbooks don't. But of course, Sandbh thinks metalloids should be nonmetals, so that appears throughout Nonmetal. And he even cites himself for it in that article. At other times they are counted as nonmetals in light of their nonmetallic chemistry, and who do we find cited but "Vernon 2020". A bit later we fnid Chemically the metalloids generally behave like (weak) nonmetals. Among the nonmetallic elements they tend to have the lowest ionization energies, electron affinities, and electronegativity values, and are relatively weak oxidizing agents. They further demonstrate a tendency to form alloys with metals., and again who do we find but "Vernon 2013". For goodness' sake. I regret supporting the FAC last time, should've researched the textbooks some more. Double sharp (talk) 21:23, 27 November 2022 (UTC)"

Thanks for that.

It has been known for over 120 years that metalloids behave chemically like nonmetals.

When I compiled Lists of metalloids I recall that only 40% of the 500 or so books I examined mentioned metalloids or semimetals in their indexes. The rest of the textbooks presumably distinguished only between metals and nonmetals. 40% is nothing to sneeze at yet it may be that the significance of a class of "in between" elements is overstated.

The nonmetal article says:


 * "Since the metalloids occupy "frontier territory" (Russell & Lee 2005, p. 419) where metals meet nonmetals, their treatment varies from author to author. Some consider them separate from both metals and nonmetals; some regard them as nonmetals (Hampel & Hawley 1976, p. 174) or as a sub-class of nonmetals (Goodrich 1844, p. 264; The Chemical News 1897, p. 189; Hampel & Hawley 1976, p. 191; Lewis 1993, p. 835; Hérold 2006, pp. 149–50). Other authors count some of them as metals, for example arsenic and antimony, due to their similarities to heavy metals (Tyler 1948, p. 105; Reilly 2002, pp. 5–6).^ Metalloids are here treated as nonmetals in light of their chemical behavior, and for comparative purposes."


 * ^ Jones (2010, pp. 169–71) takes a philosophical or pragmatic view to these questions. He writes: "Though classification is an essential feature of all branches of science, there are always hard cases at the boundaries. The boundary of a class is rarely sharp... Scientists should not lose sleep over the hard cases. As long as a classification system is beneficial to economy of description, to structuring knowledge and to our understanding, and hard cases constitute a small minority, then keep it. If the system becomes less than useful, then scrap it and replace it with a system based on different shared characteristics".


 * "The dashed line around the metalloids denotes that, depending on the author, the elements involved may or may not be recognized as a distinct class or subclass of elements. Metals are included as a reference point."

So there are ten citations here.

The citations of my 2013 (50 cites) and 2020 (6 cites; 15,910 accesses) articles represent a convenient way of referring to the various supporting citations therein (12 via 2013; 7 out of 78 in 2020). I should fix the 2013 cite since the cite involved was to the dozen alloying references in the metalloid article.

Re:


 * "For goodness' sake. I regret supporting the FAC last time, should've researched the textbooks some more."

At the FAC nomination you helpfully wrote:


 * "...Thanks for the reminder; well, I gave it a full read-through, so indeed, I'm happy to support now. It's an enjoyable read!"

I don't know what you would've gotten out of researching textbooks some more.

--- Sandbh (talk) 02:30, 2 December 2022 (UTC)
 * Lumpers and splitters. EEng 12:48, 4 December 2022 (UTC)
 * Sure, but when it's common to "split", but the article "lumps", and the main author cites himself for "lumping", we surely need to be more nuanced about it. Double sharp (talk) 15:02, 4 December 2022 (UTC)
 * These figures surely make it more rather than less necessary to check what textbooks actually do. You refer to your own research checking them, and then you say you don't know what I would've gotten out of doing it myself. Huh? Double sharp (talk) 15:02, 4 December 2022 (UTC)

Which article are we discussing: Metalloid or Nonmetal?

Double sharp, I don't know what you would've gotten out of checking 500 or so textbooks aside from what I found which was that the concept of a "metalloid" (in its modern, post-Berzelius sense) has a long history but its usage and application is inconsistent.

--- Sandbh (talk) 23:00, 4 December 2022 (UTC)

Request for admin help
I recently manually reverted the addition of unrelated content to Naming conventions (chemistry). Subsequently my reversion was reverted by u|DePiep for an unrelated reason.

Subsequently I posted a request at DePiep's talk page saying that as the content I reverted has nothing to do with naming conventions I sought his agreement to (re)remove that content.

DePiep replied at Talk:Periodic table with content essentially unrelated^ to my request seeking his agreement to remove the subject content on the grounds that it is not related to naming conventions.


 * ^ aside from saying, "While maybe not exactly "naming convention"

thank you, Sandbh (talk) 11:47, 4 December 2022 (UTC)
 * Speaking as the editor who added it to the page in the first place before this reversion sequence, I guess I should explain why I did that for context. Basically, I considered it to be a naming convention about what "group 3" means on WP and how to illustrate it. Article content is addressed by naming conventions as well. Furthermore, it seemed to be a natural follow-on to the previous section about how to name the groups of the periodic table on WP, as that alone does not fully clarify what "group 3" means (there is some variation on that in sources). Considering that the relevant standards organisation (IUPAC) saw fit to address both questions (how to name groups and what "group 3" means) in the same report, I saw no reason why we shouldn't do likewise. Lastly, as DePiep later said, this comes up often enough that it seemed prudent to put last year's consensus in the MOS. Anyway, that's why I first put it there. Double sharp (talk) 12:04, 4 December 2022 (UTC)
 * I object to this description by Sandbh. It does not reflect the actual talkflows, nor does it give a sincere overview of edits, arguments & replies made. Whether this is done by sloppyness or by gaming-the-system is not of interest now. OTOH I don't feel compelled, invited nor safe to engage in this thread. I will unfollow this page. DePiep (talk) 12:57, 4 December 2022 (UTC)
 * I'm always amused when people say they don't feel "safe". What in the world can be the safety hazard of editing Wikipedia? EEng 13:15, 4 December 2022 (UTC)
 * This appears to be a (MOS) content dispute and not something that requires any administrator action. Nthep (talk) 16:50, 4 December 2022 (UTC)

Thanks for the prompt response Nthep.

I sought help out of concern WP:BRD wasn't being followed. After my revert was reverted by DePiep (in breach of WP:BRD), I attempted to reach agreement with him via discussion at his talk page. This was unsuccessful. Hence my help request.

Re: "This appears to be a (MOS) content dispute", it isn't a MOS content dispute as such. It's rather to do with content relevance. The content, which appears on Naming conventions (chemistry), intrinsically has nothing to do with naming conventions in chemistry. The structure of the section in question looks like this:


 * 3	The periodic table
 * 3.1	Naming groups
 * 3.2	The scandium group
 * 3.3	18 vs 32 columns
 * 3.4	Categorising elements

The content involved comprises sections 3.2 and 3.4 and seeks to effectively MOS "proscribe" the composition of group 3, a proscription which has nothing to do with naming conventions.

In contrast, sections 3.1 and 3.4 are completely appropriate for a section of the MOS dealing with naming conventions in chemistry.

Could you please reconsider your impression that this appears to be a (MOS) content dispute and not something requiring any administrator action? I'm only seeking to revert the content involved without the threat of re-revert. I follow WP:BRD and presume this is not too much to expect from other editors. --- Sandbh (talk) 23:44, 4 December 2022 (UTC)
 * How exactly do you get that the composition of group 3 is somehow not a naming convention while categorising elements is one? In neither case is the title affected, only the content.
 * I'm OK with moving all the periodic table issues to MOS:CHEM instead, but the clear consensus for such a group 3 presentation clearly warrants that they be there somewhere. Double sharp (talk) 03:33, 5 December 2022 (UTC)
 * stop doing content discussions on a usertalkpage. DePiep (talk) 08:07, 5 December 2022 (UTC)

Sandbh, sorry but I still don't see anything here that requires administrator action. Admins do not resolve disputes about content, whether that is article content, policy content, MOS content. Admin responsibilities are mostly about user conduct, see MOPRIGHTS. I'm not seeing anything here that matches anything on that list. What I am seeing in a discussion that appears to be spreading over several pages making it difficult for anyone to follow or contribute to. I suggest these various discussions get bundled together in one place (not here) or start afresh with a clear statement of what the issues are and if you can't get a consensus then look towards the various options at dispute resolution. Nthep (talk) 09:09, 5 December 2022 (UTC)

Request for help
Hi, I know your field of expertise lies within the chemical sciences, but I also know you are an excellent editor who is good at pulling out self promoting nonsense. As such I would like to ask for some help please with Electroencephalography, the article is full of awful self promotion, references to primary material etc and is a very important topic in neuroscience. I've begun rewriting some of it but there is a lot to do. There is a huge amount of literature reviews on a wide range of relevant things, so finding material should not be too hard, but more than happy to throw review articles your way if you need them. Hope you decide to help and thanks for reading this! EvilxFish (talk) 04:02, 20 December 2022 (UTC)

Talkpage breaking
I have reverted your posting on WT:ELEMENTS,. It was a disruption of the talkpage, an RfC no less. There is not fruit in 'discussing' such behaviour as far as we can see. Consider this post here as a warning too. Also, you have multiple older non-talkpage posts in there you were asked repeatedly to redact. Those too, as you left them behind, could be considered a grave disruption of the RfC. DePiep (talk) 04:14, 27 February 2023 (UTC)


 * ping, as technically involved . DePiep (talk) 04:16, 27 February 2023 (UTC)
 * See also the editsummary, ICYMI. DePiep (talk) 04:48, 27 February 2023 (UTC)
 * WP:DISRUPTIVE. Final call: you are strongly advised to redact your today's post. Issues have been pointed out to you, and can be corrected by you before saving. You have been warned. -DePiep (talk) 05:32, 27 February 2023 (UTC)
 * Fair enough. -DePiep (talk) 05:37, 27 February 2023 (UTC)

Error in periodic table
Hello. File:PT blocks and 1st rows.png doesn't list Thorium in the f-block and shifts each following element over by one, with Lawrencium shown twice. Is that something you can correct? Dhtwiki (talk) 04:35, 23 April 2023 (UTC)
 * Thanks very much. It does now. Sandbh (talk) 05:11, 23 April 2023 (UTC)

New message from Jo-Jo Eumerus
You are invited to join the discussion at User talk:Jo-Jo Eumerus § TRAPPIST-1. Jo-Jo Eumerus (talk) 10:14, 24 April 2023 (UTC)
 * Greetings, just noting that I've put some more comments both there and on Talk:TRAPPIST-1 Jo-Jo Eumerus (talk) 09:44, 26 April 2023 (UTC)

TRAPPIST-1
Greetings, at the risk of sounding impatient, but is this offer of a copyedit still valid? Jo-Jo Eumerus (talk) 15:37, 2 May 2023 (UTC)


 * Hi Jo-Jo. The offer is still valid subject to IRL commitments. In the meantime please do follow up with Tony1. I've booked 2 hours for copyediting tomorrow morning my time. Let's see how much I can get through. Sandbh (talk) 03:52, 3 May 2023 (UTC)
 * Thanks. I did ask Tony and they said that they don't work on FA candidates. Jo-Jo Eumerus (talk) 07:48, 3 May 2023 (UTC)
 * Tx; I'll carry on. Sandbh (talk) 07:56, 3 May 2023 (UTC)
 * Thanks for the edit. I've resolved your comments, I think; feel free to continue if there are other edits to be done. Jo-Jo Eumerus (talk) 07:12, 4 May 2023 (UTC)

Nonmetal (physics) moved to draftspace
An article you recently created, Nonmetal (physics), is not suitable as written to remain published. It needs more in-depth coverage about the subject itself, with citations from reliable, independent sources in order to show it meets WP:GNG. It should have at least three, to be safe. And please remember that interviews, as primary sources, do not count towards GNG. (?) Information that can't be referenced should be removed (verifiability is of central importance on Wikipedia). I've moved your draft to draftspace (with a prefix of " " before the article title) where you can incubate the article with minimal disruption. When you feel the article meets Wikipedia's general notability guideline and thus is ready for mainspace, please click on the "Submit your draft for review!" button at the top of the page. Onel 5969  TT me 11:20, 14 May 2023 (UTC)

Note re nonmetal article
There is a quotation in nonmetal that says:
 * "The stability of the carbon—carbon bond ... has made it the first choice element to scaffold biomolecules. Hydrogen is need for many reasons; at the very least, it terminates C–C chains. Heteroatoms (atoms that are neither carbon nor hydrogen) determine the reactivity of carbon-scaffolded biomolecules. In ... life, these are oxygen, nitrogen and, to a lesser extent, sulfur, phosphorus, selenium, and an occasional halogen."

Two questions: YBG (talk) 04:29, 22 May 2023 (UTC)
 * 1) Does the original say “hydrogen is need” or “hydrogen is needed”? If the former a “sic” should be added. If the latter, of course, it should be corrected.
 * 2) is the parenthetical explanation of heteroatoms in the original? If not, then square brackets should be used to indicate an addition not in the original.
 * Thanks YBG. The full quote is:


 * The stability of the carbon–carbon bond at 273–373 K has made it the first choice element to scaffold biomolecules. Even in Terran biochemistry, other elements are required. Hydrogen is needed for many reasons; at the very least, it terminates C–C chains. Heteroatoms (atoms that are neither carbon nor hydrogen) determine the reactivity of carbon-scaffolded biomolecules. In Terran life, these are oxygen, nitrogen and, to a lesser extent, sulfur, phosphorus, selenium, and an occasional halogen.

I have thus corrected the need v needed mistake. --- Sandbh (talk) 02:12, 23 May 2023 (UTC)

Would it be ok …
... with you if I collapsed our side discussion in the RfC with a title “side discussion about RfC venue”? I’m asking at both User talk:Sandbh and User talk:Redrose64 YBG (talk) 14:44, 24 May 2023 (UTC)


 * Collapsing may not be needed. Since the next response came between Sandbh’s response and our discussion, I simply added a === header to separate the discussion. YBG (talk) 15:46, 24 May 2023 (UTC)

Hey
hey. Thanks for your kind words at WT:FAC. &sect; Lingzhi (talk&#124;check refs) 11:38, 28 May 2023 (UTC)

New message from Jo-Jo Eumerus
You are invited to join the discussion at Wikipedia:Featured article candidates/TRAPPIST-1/archive3. Jo-Jo Eumerus (talk) 15:48, 21 June 2023 (UTC)

TRAPPIST-1
Noting that I did reply to your comments on the FAC talk page. JoJo Eumerus mobile (main talk) 18:40, 30 August 2023 (UTC)


 * And replied/handled further comments. Jo-Jo Eumerus (talk) 09:13, 31 August 2023 (UTC)

Nonmetal lede pic suggestion
What would you think of putting the H/At daggers in the full PT picture and moving that part of the legend to below the full PT? YBG (talk) 04:42, 27 September 2023 (UTC)


 * I tried two variations, one without the full periodic table (here) and one with, per your suggestion. Which do you prefer? Sandbh (talk) 08:13, 27 September 2023 (UTC)
 * Ta. It actually made me think of yet another option.
 * Image 1 title: Nonmetals in the periodic table
 * Image 1: Full PT with no daggers and a question marks on grey At and 3 white super heavies.
 * Image 1 caption: Considered a nonmetal /// Usually/always /// Sometimes
 * Image 2: excerpt with daggers
 * Image 2 caption: H /// At
 * YBG (talk) 10:25, 27 September 2023 (UTC)


 * I went the whole hog and replaced the image with a condensed table spanning the 18 groups. I recall you long ago requested something like this in one of the FACs. Sandbh (talk) 06:30, 29 September 2023 (UTC)
 * Wow! This really pops. It is similar to what I had in mind back then, but a significant improvement to what I had envisioned. I especially like how it shows up as hovertext in other articles. Here are some suggested improvements, in rough order of importance.
 * The dashed border around Cn, Fl, and Og is barely visible. I think it should go around the whole box as it does for At, and it would be helpful if the border (but not the text) were the same color for all four of these elements. Done.
 * Suggested changes for the elided columns:
 * The last cell needs to be Lr-Rg (not Lr-Cn) and should be properly aligned with the element symbols to the left and right. Done.
 * As you are not showing a lanthanide and actinide block, you could change the last two to La-Au/Lr-Rg and change the header to an elipsis.
 * Alternately, you could also elide group 2 so that the column reads 2-11/Be/Mg/Ca-Cu/Sr-Ag/Ba-Au/Ra-Rg. This eliminates the lanthanide/actinide issue - the table could equally be seen as an elided 32-column table or an elided 18-column table with the La/Ac footnote blocks omitted.
 * Whatever you decide about the other points, you could also consider, for those cells with element ranges, putting element number ranges where there are element names, so 2nd line would be either 21-29/39-47/71-78/103-111, or 21-29/39-47/57-79/89-111, or Beryllium/Magnesium/20-29/38-47/56-79/88-111 depending on whether you decide to include lanthanides/actinides or group 2 in the elided column.
 * I think the "sometimes" nonmetals might look nicer with the same border as the "usually/always" ones. Done.
 * The metals look just fine with no border, but might be better with a slightly darker gray text. Done.
 * YBG (talk) 12:12, 29 September 2023 (UTC)

Thank you very much ! The focus of the image is on nonmetals so I trimmed the extra legend boxes. It look like we may have gotten to a happy medium now. Sandbh (talk) 03:35, 30 September 2023 (UTC)


 * Yes, recognizing that the focus here is nonmetals has helped us come a long way. A few additional comments, again, in descending order of significance.
 * With regard to the elided elements, either you misunderstood one of my suggestions or you chose a completely different option, adding daggers to Ba/Ra and footnotes for the La/Ac series. IMO this is too much detail for a table focused on the nonmetals and significantly worse than the previous version that completely ignored La/Ac. If neither of my previous suggestions works, would you consider reverting back to the previous version (minus the obvious errors)? And if not that, then maybe add an extra column for La-Yb/Ac-No (or La.../Ac...), essentially making it a condensed 32-column table. I'm not particularly happy with this last idea, but IMO it's significantly better than the daggers and footnotes.
 * You've made the dashed borders of At/Cn/Fl/Og match each other as requested, but its gray still seems too subtle. Black of course would be too much, but maybe something in between so the three superheavies stand out slightly? As potential nonmetals, they deserve a bit more attention than the current gray border gives them.
 * You've changed the At color from "sometimes" gray to half "usually/always" tan and half "metal" white. I would have expected the non-white half to have been a "sometimes" gray. I'm not asking for a change, it doesn't really matter to me.
 * Thanks for your good work. YBG (talk) 05:01, 30 September 2023 (UTC)

Cheers.

I've trimmed the Ln/An from the image; made the four dashed boxes thicker, and added a footnote to the title re the Ln/An. How's that looking now?

Astatine is tricky. It was referred to as a metal by the team that first synthesized it. A few other folks referred to its metallic status but, since it was a halogen and so little was known about it, it came to be usually regarded as a nonmetal by default. It has occasionally been counted as a metalloid. In lists of metalloids it has an appearance frequency of 40% compared to 86–99% for B, Si, Ge, As, Sb, Te. The thing about the grey boxes is that they don't necessaily mean that if the element concerned is not counted as a nonmetal that it is counted as a metalloid: Ge, As and Sb are sometimes instead counted as metals. I'll try showing the At box as gold, grey and white. Sandbh (talk) 05:45, 30 September 2023 (UTC)

At is now tricolor. Sandbh (talk) 06:20, 30 September 2023 (UTC)


 * Thanks again. I reckon the tricolor is a bit over the top esthetically. Besides, gold/tan doesn't really apply - by no one's standards is it "usually/always counted as a nonmetal". Given what you way about Ge/As/Sb, it seems that the solid gray applies to At also. It is clearly true that it is "sometimes counted as a nonmetal". YBG (talk) 07:41, 30 September 2023 (UTC)


 * Good. I've now shown At with a white background and reinstated the caption note as to what's going on. Sandbh (talk) 13:41, 30 September 2023 (UTC)


 * Consider the situations of Cn/Fl and Ge/As/Sb. As I understand it, the former are (almost?) never counted as nonmetals, and the latter are sometimes counted as nonmetals and sometimes counted as metals. Have I described the situation correctly? The pic currently shows At to be more like the former than the latter. Is that what you intend? YBG (talk) 17:26, 30 September 2023 (UTC)

October 1st arbitrary break

 * For Cn and Fl there is not enough known about them to make a completely reliable call. We do know that relativistic effects enter the picture in the lower rows which explain why Po is a metal and At is expected to be a metal. Barring anything more insightful it's fair to presume that the default status for Cn and Fl is as metals.
 * For Ge, As and Sb, maybe close to half of authors count them as metalloids. The other half fall-back on the zig-zag line and therefore count Ge and Sb as metals and As as a nonmetal. The zig-zag line is not a reliable indicator. We know that Ge is a semiconductor which means that it is not a metal. It has been known that Sb has a predominately nonmetallic chemisty for about 120 years. While in old chemistry, the distinction between metals and nonmetals was based purely on physical characteristics it was later realised that chemical properties also had to be taken account of. On the basis of physical + chemical properties, Ge, As and Sb are nonmetals. --- Sandbh (talk) 06:07, 2 October 2023 (UTC)
 * Coloring At as a solid color is an improvement over the multi-colored options previous used; however, I have two problems with its current white coloration.
 * The white color does not follow the definitions given by the legend, which says
 * (a) tan: elements "usually/always counted as a nonmetal"
 * (b) gray: elements "sometimes counted as a nonmetal"
 * (c) white: (implied) elements not meeting conditions (a) or (b) (i.e., those never counted as a nonmetal)
 * At does not satisfy (a) but clearly satisfies (b). Yes, you treat it as a metal in this article, but isn't it true that it is "sometimes counted as a nonmetal" in the literature? So why is it not colored gray? Yes, it is clearly not in the same category as those elements commonly called metalloids, but that distinction is provided by the dashed border.
 * The white-color-plus-dashed-border lumps At in with Cn/Fl/Og, which are clearly very different.
 * I recognize that the situation of At is different from those elements currently colored gray, but the dashed border gives us a clear way to indicate this subtlety.
 * This is why I prefer the At footnote to say "treated in this article as a metal" instead of "At is treated here as a metal". How At is treated "in this article" is one thing - and I think you've made the right decision. But to say "treated here" is a bit ambituous - it could mean "in this article" or "in this table". How At is treated "in this PT extract" should be based not on how it is treated in the rest of the article, but on the definitions given in the legend.
 * YBG (talk) 01:45, 4 October 2023 (UTC)
 * Tx; I made that change. --- Sandbh (talk) 11:57, 5 October 2023 (UTC)
 * Thank you for that. Have you considered the larger issue I raised above in both points 1 and 2? As I see it, the current coloring implies that the literature never counts astatine as a nonmetal. I don’t think this is accurate. YBG (talk) 01:11, 6 October 2023 (UTC)


 * Yes, At has usually been counted as a nonmetal, sometimes as a metalloid, and occasionally as a metal. Effectively, nearly all authors did not do sufficient research into the nature of At, instead classifying it as nonmetal due to its status as a halogen and the "publish or perish" imperative. The latter was way more important than diving into the nature of such a rare and highly radioactive element. Here's some more background to At as a metal, including a timeline:


 * The bulk properties of astatine remain unknown as a visible quantity of it would immediately self-vaporize from the heat generated by its radioactivity. It remains to be seen if, with sufficient cooling, a macroscopic quantity could be deposited as a thin film.


 * Qualitative and quantitative assessments of its status, including having regard to relativistic effects, have been consistent with it being a metal:


 * 1940. Astatine was judged to be a metal when it was first synthesized. That assessment was consistent with some metallic character seen in iodine,  its lighter halogen congener.


 * 1948. Seaborg GT, "The eight new synthetic elements", American Scientist, vol. 36, no. 3, p. 368:


 * "They have found that it behaves in many ways like a metal and is more electropositive in character than is the case for the other halogens. This is not surprising in view of the pronounced trend in this direction as we go toward the heavier end of the halogen group, but the possible extent of this effect was apparently overlooked in the chemical searches which have been made for this element in its natural form."


 * 1949. Bladel WJ 1947, Nuclear Chemistry: Notes on a Series of Lectures, Atomic Energy Commission, Oak Ridge, Tennessee, pp. 51–52:


 * "Examination of the periodic chart shows that astatine falls in the seventh group with the halogens, and hence would be expected to resemble chlorine, bromine, and iodine in its chemical behavior. In fact it was so sought by chemists for many years who missed finding it because they worked from this assumption. Actually the astatine is much more metallic than even iodine, and in this behavior it resembles that of the elements in Group VI and Group III. In Group VII, bromine, iodine, and astatine are analogous to selenium, tellurium, and polonium, of Group VI and arsenic, antimony, and bismuth of Group III. The last-named element of each of these three triads displays considerably more metallic character than do the preceding two.


 * Astatine is not dissolved by CCl4 as is iodine. Its properties follow closely those of the other metals. It is precipitated as the sulfide along with bismuth, mercury, cadmium, and copper. The astatine is not volatile with iodine, can be separated by the water-CCl4 binary extraction system, and can not be precipitated by silver ion as an astatinide. Something is known about the reduction of astatine. It can be reduced by SO2 or zinc. Immersion of a copper plate in an astatine precipitates the astatine as a metal on the plate. This shows its ease of reduction, since copper is a quite weak reducing agent."


 * 1950. Kleinberg J, "Unfamiliar oxidation states and their stabilization," Journal of Chemical Education, vol. 27, no. 1, p. 32:


 * "The behavior of astatine, in many of its reactions, is that of a typical metal; for example, hydrogen sulﬁde precipitates element 85 quantitatively as sulﬁde in hydrochloric acid solution up to 6 normal. At ﬁrst glance, this is extremely surprising, but it appears less so when it is realized that iodine, the element above 85 in the family, also possesses some metallic character istics. Indeed, compounds in which iodine exists as a unipositive ion stabilized by coordination with organic amines have been prepared (7). The behavior of astatine is also in line with the increased metallic character of the elements in a given group with increasing atomic number from carbon to lead, nitrogen to bismuth, and oxygen to polonium."


 * 1954. Fearnside K, Jones EW & Shaw EN, Applied Atomic Energy, Philosophical Library, New York, p. 102:


 * "The position of 85 in the periodic table is that of a halogen, yet astatine has most of the chemical properties of a metal."


 * 1956. Encyclopædia Britannica, vol. 6, p. 823:


 * "Astatine may well be a metal"


 * 1972. Batsanov calculated astatine would have a band gap of 0.7 eV [which is metalloid- and hence nonmetal-territory] (but see the 2013 entry)


 * 1975. Furse AJ & Rendle GP, The Pattern of Chemistry, Edward Arnold, London, p. 82:


 * "Probably the most important difficulty would be to decide how much different astatine is from iodine, i.e. how far the trend has gone. Perhaps astatine has such a high melting point that we ought to consider the possibility that it is a metal."


 * 1983. Edwards and Sienko speculated that, on the basis of the non-relativistic Goldhammer-Herzfeld criterion for metallicity, astatine was probably a metalloid. As the ratio is based on classical arguments  it does not accommodate the finding that polonium (cf. 2006 entry following) adopts a metallic (rather than covalent) crystalline structure, on relativistic grounds. Even so it offers a first order rationalization for the occurrence of metallic character amongst the elements.


 * 2002. Siekierski and Burgess presumed astatine would be a metal in the context of some of the properties of iodine.


 * 2006. Restrepo et al., on the basis of a comparative study of 128 known and interpolated physiochemical, geochemical and chemical properties of 72 of the elements, reported that astatine appeared to share more in common with polonium (a metal) than it did with the established halogens and that, "At should not be considered as a halogen." In so doing they echoed the 1940 observation that, "The chemical properties of the unknown substance are very close to those of polonium."


 * 2010. Thornton and Burdette observed that "Since elements at heavier periods often resemble their n+1 and n-1 neighbours more than their lighter congeners, eka-iodine [astatine]...was expected to be radioactive and metallic like polonium."


 * 2013. Hermann, Hoffmann, and Ashcroft predicted At would be an fcc metal, once all relativistic effects are taken into account, and that it would have a band gap of 0.68 eV (cf. Batsanov) if only some of these effects were taken into account.

I guess I'm saying that all of the assessments of At as a nonmetal are unreliable. Hence it shows as a metal i.e., a post-transition halogen metal.

Alternatively there is always the tricolor version, which corresponds to At usually being counted as a nonmetal, sometimes as a metalloid, and occasionally as a metal. --- Sandbh (talk) 06:59, 6 October 2023 (UTC)


 * You are arguing that At should be treated as a metal, and to that you have no argument from me. There is no need to cite 13 references. I already agree that At is best excluded from the scope of this article. But that is not the point. The question at hand here is, how should astatine be colored in this graphic?
 * First, consider what the legend does NOT say.
 * It does NOT say nonmetal / metalloid / metal (as hinted in your final paragraph)
 * It does NOT say "as treated in this article"
 * It does NOT say "counted as a nonmetal in sources deemed to be reliable"
 * It simply says, and so that is the basis the elements should be colored.
 * Second, consider the three colors. Two are explicitly defined:
 * By implication the third category means "NEITHER counted as a nonmetal NOR  counted as a nonmetal". If this category were explicitly labeled (which is not necessary), I would label it
 * never/almost never counted as a nonmetal.
 * Notice that these three color groups are mutually exclusive and jointly exhaustive. An element cannot be both and at the same time only . It cannot qualify as either of these two colors and in addition qualify as white, which by clear implication means "neither of the above two categories". To use multiple colors in a single cell is to imply a logical fallacy.
 * What color then should astatine qualify for, according to the legend? With what frequency is it counted as a nonmetal?
 * Is astatine ? Clearly not.
 * Is astatine never/almost never counted as a nonmetal? Clearly not.
 * Is astatine ? Clearly so.
 * So with this legend we are forced to color astatine the same as B/Si/Ge/As/Sb/Te. But it is clearly in a different situation from these six elements. We have rightly added a marking and a clarifying footnote.
 * Would the dashed gray border on a tan cell be a clear enough distinction between At and B/Si/Ge/As/Sb/Te? Perhaps, but I think it would be best to make the border stronger – either wider or darker or both.
 * What about the clarifying footnote? Is it strong enough? Perhaps not. This footnote as it exists indicates clearly enough that At is not a subject of this article. But it could be made stronger if desired. Here is the place where one could state that although it is sometimes counted as a nonmetal, overall the literature indicates that it is best treated as a metal.
 * So, in summary, astatine should be colored tan like B/Si/Ge/As/Sb/Te, but the marking (and perhaps the footnote) should be strengthened. YBG (talk) 12:17, 10 October 2023 (UTC)
 * Is astatine ? Clearly so.
 * So with this legend we are forced to color astatine the same as B/Si/Ge/As/Sb/Te. But it is clearly in a different situation from these six elements. We have rightly added a marking and a clarifying footnote.
 * Would the dashed gray border on a tan cell be a clear enough distinction between At and B/Si/Ge/As/Sb/Te? Perhaps, but I think it would be best to make the border stronger – either wider or darker or both.
 * What about the clarifying footnote? Is it strong enough? Perhaps not. This footnote as it exists indicates clearly enough that At is not a subject of this article. But it could be made stronger if desired. Here is the place where one could state that although it is sometimes counted as a nonmetal, overall the literature indicates that it is best treated as a metal.
 * So, in summary, astatine should be colored tan like B/Si/Ge/As/Sb/Te, but the marking (and perhaps the footnote) should be strengthened. YBG (talk) 12:17, 10 October 2023 (UTC)
 * So, in summary, astatine should be colored tan like B/Si/Ge/As/Sb/Te, but the marking (and perhaps the footnote) should be strengthened. YBG (talk) 12:17, 10 October 2023 (UTC)
 * So, in summary, astatine should be colored tan like B/Si/Ge/As/Sb/Te, but the marking (and perhaps the footnote) should be strengthened. YBG (talk) 12:17, 10 October 2023 (UTC)

Thank you.

These days I guess about 50% of authors refer to metalloids. The appearance frequencies of metalloids in lists of metalloids are 86–99% for B, Si, Ge, As, Sb, Te; and 40% for At. So, At is recognised as a metalloid 0.50 × 0.40 = 20% of the time. The rest of the time At is usually counted as a nonmetal and occasionally as a metal. So I feel it should therefore be coloured as a nonmetal, with a stronger marking around it.

Would that work for you? --- Sandbh (talk) 01:23, 11 October 2023 (UTC)


 * The legend does not offer us with the choice of coloring an element as a nonmetal or as a metalloid. These are not the categories that the legend currently offers. Whichever one of these statements you think is most accurate:
 * Astatine is usually/always counted as a nonmetal.
 * Astatine is sometimes counted as a nonmetal.
 * Astatine is NEITHER usually/always counted as nonmetal, NOR IS astatine sometimes counted as a nonmetal (which I think means the same as saying that astatine is never or almost never counted as a nonmetal).
 * Whichever one of these statements is true should determine the color of astatine. I was under the impression that it was more like “sometimes” than “usually/always”, but I you are more familiar with the literature than I, so I will leave it to you to determine which statement is the best representation of reality.
 * Thanks for patiently hearing me out. YBG (talk) 03:38, 11 October 2023 (UTC)
 * Thanks for your careful attention to these details.
 * I'll colour At as a "usually counted as a nonmetal", but with a grey font like the other metals, and a stronger border. --- Sandbh (talk) 03:45, 11 October 2023 (UTC)
 * OK, that's done. --- Sandbh (talk) 04:12, 11 October 2023 (UTC)

DS arbitrary break
Pardon me for butting into this, but since I don't think this point has been raised: there is quite a difference between the situation for At, versus that for the superheavies. Firstly, with astatine, the quantities are just much more. It's currently impossible to work with more than one atom at a time for the period-7 elements. Secondly, with astatine we're basically interpolating the relativistic effects. We (as in humanity as a whole) know what Po is like, we've seen macroscopic quantities of Rn, and we're relatively familiar with the ways Ra–Es differ from Ba–Ho. For the late period 7 elements we are basically extrapolating into a situation that does not really have any precedent (the closed shells at Cn, Fl, and Og, which are incidentally why it has been wondered if they might fail to metallise). So I agree with the way this is currently handled: mention that they might be nonmetals, that that's not confirmed, and leave it at that. It also seems correct to me that they get a different colour and border from At, as the situation is different. (I think they will all be metals, but that's on the basis of limited evidence, and I'll be happy to change my mind as more trickles in.)

I'd also be careful of overselling At's metallicity. All these determinations were no doubt done very skillfully, but in one important way they are not comparing like with like. We can work with chlorine, bromine, and iodine with large quantities. For astatine this is obviously impossible. And that's important, because ultra-low concentrations lead to significant changes in equilibria already for iodine. I even think that this is why you don't see any region for At0 on the Pourbaix diagram at all: judging by the halogen trend (in which X2 becomes more stable from Cl to Br to I), and indeed Bi and Po, there ought to be such a region, but it won't show up because under the concentrations the experiments are done at you can hardly expect two At atoms together in one molecule. The point is that I wouldn't be surprised if bulk astatine would actually act a lot more like bulk iodine than trace astatine does, because trace iodine already doesn't always act like bulk iodine does. That is obviously speculation, but at least the point stands: you cannot assume that tracer behaviour is the same as bulk behaviour. Also, is it really true that chemists failed to find At because they thought it would be halogen-like? I don't think so. Chemists also failed to find Fr together with the alkali metals. By the time we got this far into finding the rare natural radioelements, chemistry simply wasn't the most important factor. Hulubei and Cauchois did have 218At, but they could not perform chemical studies; they were looking for the X-ray radiation from its decay. Instead the problem with At is that it only appears naturally as a rare side branch in the decay chains, so it's hard to find simply because it's rare. Double sharp (talk) 07:56, 11 October 2023 (UTC)


 * You're quite welcome.


 * There seem to be two threads in the literature:


 * 1. As a halogen At has been presumed to be a nonmetal (mainly by textbook authors).
 * 2. A succession of sources (i.e. in 1940; 1948; 1949; 1950; 1954; 1956; 1975; 2002; 2006; and 2010) have speculated or presumed astatine would be a metal (including on the grounds of iodine showing some near-metallic character i.e. it being silvery under white light; a 2D semiconductor; and evidence of delocalised electrons). Then, the 2013 study based on relativistic physics concluded that it would be a monatomic metal with an fcc crystalline structure.


 * Curiously:
 * Batsanov (1972) calculated astatine would have a band gap of 0.7 eV, which means it would not be a metal.
 * Hermann, Hoffmann, and Ashcroft (2013) predicted At would be an fcc metal, once all relativistic effects were taken into account, and that it would have a band gap of 0.68 eV (cf. Batsanov) if only some of these effects were taken into account.


 * The Pourbaix diagram of astatine differs from the lighter halogens in that the At+ cation ion is present.


 * That said, you raise a good point about the potential risk of basing conclusions about At on tracer level chemistry.

Re chemists failing to find At because they thought it would be halogen-like.

The supporting reference is Thornton BF & Burdette SC 2010, "Finding eka-iodine: Discovery priority in modern times", Bulletin for the history of chemistry, vol. 35, no. 2, accessed September 14, 2021:


 * "Searching for eka-iodine in substances that contained other halogens was deemed a reasonable strategy for finding the missing element by early researchers."

Allison et al. (1931) looked for At in sea water, fluorite, apatite, monazite sand (Brazilian), kainite (Stassfurt), potassium bromide, hydrofluoric acid and hydrobromic acid.


 * Allison, F., Murphy, E. J., Bishop, E. R., & Sommer, A. L. (1931). Evidence of the Detection of Element 85 in Certain Substances. Physical Review, 37(9), 1178–1180. --- Sandbh (talk) 01:23, 13 October 2023 (UTC)


 * --- Sandbh (talk) 22:59, 11 October 2023 (UTC)
 * At low concentrations, I2 (oxidation state 0) becomes less stable, and HIO (oxidation state +1) becomes more stable. (See p. 6 here.) Of course this is not proof of the At situation, but it means that it's not out of the question that At+ (also oxidation state 1) might also disappear from the Pourbaix diagram as concentration rises in favour of elemental At.
 * Strong physical metallicity of At (which seems to be the thrust of your thread #2) might not necessarily mean its chemistry is convincingly metallic. Arsenic shows that the two need not always go together. Double sharp (talk) 23:22, 11 October 2023 (UTC)


 * There is a difference between As and At in that the former is a semimetal whereas the latter is expected to a fully-fledged metal, in electronic band structure terms. If in bulk, At turns out to not form a monatomic cation in aqueous solution perhaps it will have to be regarded as being akin to some of the transition metals that don't form monatomic cations in aqueous solution. If it has an fcc structure it will probably be quite ductile, which is likely to further support its status as a metal. It could also be expected to show significant nonmetallic character, as is normally the case for metals in, or in the vicinity of, the p-block. --- Sandbh (talk) 01:03, 13 October 2023 (UTC)


 * That quote from Thornton and Burdette, to my mind, does not necessarily mean that chemists failed to find At because they thought it was halogen-like. It seems to indicate that they failed to find At because it's too unstable to occur as anything other than a uranium daughter. Chemists equally failed to find Fr in alkali metal deposits, even though that impression of its chemistry turned out to be wholly accurate. But I guess we already agree on the important thing, which is that classifying At by metallicity is something that depends not only on how you interpret "metal" but also (and quite heavily) on predictions, unlike how it would be for experimentally better-probed elements. Double sharp (talk) 10:53, 13 October 2023 (UTC)

More re legend
I would like to suggest that the comments re astatine and the superheavies be worded as follows: Thoughts?YBG (talk) 19:22, 12 October 2023 (UTC)
 * Astatine is usually counted as a nonmetal, but its nonmetal/metal status has not been confirmed. This article treats it as a metal, as relativistic effects suggest.&lt;ref name="At"/> Copernicium, flerovium, and oganesson are almost never counted as nonmetals, but their nonmetal/metal status has not been confirmed.


 * Does this imply a need to change the dashed border around At, in the PT extract, so that it's the same as the style of border around the three superheavies?


 * I feel the wording about At needs to be consistent with the wording about At in the last paragraph of the Definition and applicable elements section.


 * How about:

&thinsp;The metallic or nonmetallic status of astatine (At) is not clear. While it is usually counted as being nonmetallic, relativistic effects suggest it will be a metal.[1] &thinsp;One or more of copernicium, flerovium, and oganesson may turn out to be nonmetallic however their status has not been confirmed.
 * — Preceding unsigned comment added by Sandbh (talk • contribs) 03:33 October 13, 2023 (UTC)

I’m not agitating for the borders to be identical; the simple dash was the only thing available. But it might be good to have them correspond to what’s in the notes.

As to the wording, yes, I think it would be good to have it correspond to what’s in the article; thank you for pointing that out. I would like to also incorporate something from the language of the legend to explain our choice of shading. I will work on better wording in the next few days.

YBG (talk) 05:48, 13 October 2023 (UTC)


 * I've gone ahead and adjusted the image and the captions. Looks good. Sandbh (talk) 06:21, 13 October 2023 (UTC)

Precious anniversary
--Gerda Arendt (talk) 07:42, 4 October 2023 (UTC)

Concern regarding Draft:Nonmetal (physics)
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Just as a hypothetical
Based on our discussion about At, I'm now curious about how you'd deal with these hypotheticals. Consider it a question on how you'd balance physics and chemistry considerations.


 * if As and Sb had been true metals by band structure at STP (not semimetals), but otherwise had the same chemistry, would you consider them metals?
 * if Sn only had the grey allotrope at STP, but otherwise had the same chemistry, would you consider it a metal?

Double sharp (talk) 12:02, 14 October 2023 (UTC)


 * I've had to think at length about your questions.


 * The answer seems to be that any element having a metallic band structure is counted as a metal. For the semimetals, they are counted as metals if they form a cation in aqueous solution or, if not, as nonmetals.


 * Grey Sn is a semimetal, that forms a cation in aqueous solution. Therefore, I'd count it as a metal, similarly to Bi, another semimetal that forms a cation in aqueous solution.


 * For As and Sb it first seems relevant to consider that Nb, Ta, W, Tc, Re, Os and Ir don't appear to form cations in aqueous solution. Yet they are still counted as metals. In the old days this would've been due to their high densities. These days, having clearly overlapping valance and conduction bands seems to be the key.


 * As and Sb are not so dense (5.73 g/cc; 6.69) and do not form cations in aqueous solution within the normal range of pH values (0–14). In hypothetical metallic As and Sb the stronger metallic bonding would presumably cause the atoms to be held together more tightly, resulting in a denser material. Looking at their behaviour under pressure it seems that As metallizes at 25 GPa (primitive cubic) and Sb at 28 GPa (bcc). I note that black arsenic "metallizes" at 2.2 GPa however this is instead a transition from semiconductor to semimetal.


 * On the basis of the greater packing efficiencies, the density of hypothetical metallic As would be 7.8 g/cc and Sb would be 11.1 g/cc. That places them in the same league as Nb (8.57 g/cc).


 * I presume there would be a higher electron density in the conduction band, leading to a greater number of free electrons. So, whereas the densities of charge carriers in the semimetals carbon (as graphite, in the direction of its planes), arsenic, antimony and bismuth are 3 cm−3, 2 cm−3, 5 cm−3 and 3 cm−3 respectively, the concentration of electrons in metals usually exceeds 1022 cm−3.


 * With the increased electron density in the conduction band, the effective nuclear charge experienced by the valence electrons would be reduced. This is because the positively charged protons in the nucleus are shielded by the presence of the additional electrons. As a result, the valence electrons would be less strongly attracted to the nucleus. I thus expect that hypothetical true metallic As and Sb would be more inclined to form cations in aqueous solution.


 * I suppose the EN of As and Sb would decrease too. --- Sandbh (talk) 01:29, 17 October 2023 (UTC)
 * That's an interesting approach, thanks for your answer.
 * There are actually some semimetals in the PT that are far from the metal-nonmetal transition line: Be, Sr, and Yb. Considering that all three are close-packed, and that Sr and Yb are pretty clear metals I'm not sure the difference really means that much.
 * P.S. some food for thought regarding the chalcogens: molten Se and Te are metals, and the short-range order is cubic, like Po. OTOH, Po is cubic at low temperature (alpha phase), reverts to the Se and Te structure at higher temperature (beta phase), and then goes back to local cubic structure just above the melting point. I haven't yet been able to check if beta-Po is a metallic conductor or not. Double sharp (talk) 13:58, 17 October 2023 (UTC)

interesting article on metallicity
Not sure if you've seen this one. :) Double sharp (talk) 04:55, 22 October 2023 (UTC)
 * Tx muchly, I'd seen that one a while back, and will look at it again to see if I missed anything.


 * A few days ago I stumbled on this article which has made me think I should seek to write an article for them on "Which elements are nonmetals: An exercise in history, classification science and uncertainty" or a title along those lines. Sandbh (talk) 06:00, 23 October 2023 (UTC)

Walls of text
As a personal favor to me, I would greatly appreciate it if your talk page replies were briefer. Even hatted off, it is very hard to follow on my smartphone where I do a lot of editing.

You just have said “I have X more sources” and I would have taken your word for it. With no access to the sources, I generally take your word for things - unless Double sharp contradicts you.

On top of that, you missed my point about the term “commonly”. I was not saying that three sources are not sufficient for WP to say “commonly” and so asking for more. I was asking if any of those sources use the word “commonly”. I’m not saying that’s necessary for WP to say “commonly”, I just want to understand well enough to evaluate the text.

Anyway, my larger point here was to ask that you avoid such long posts.

I do wish to commend you for your spirit of collaboration and willingness to adjust the article before going back to FAC. You may pick up one or two co-nominators!

Thanks! YBG (talk) 15:08, 29 October 2023 (UTC)


 * Thanks. I'll bear your request in mind.


 * Two questions were put about "commonly", rather than one:


 * "Do the sources for the 1st sentence in the comparison all say this comparison is “commonly drawn? Or is “commonly” justified by the fact that three sources are listed?"


 * I can't recall sources that use the adjective "commonly" to refer widely accepted observations such as that the elements are divided into metals and nonmetals; or that the periodic table is a representation of the periodic law; or that the counterparts of the alkali metals are the halogens.


 * There is instead a long history in the literature of, for example, a generalized pattern across the periodic table of highly active to less active (even noble) metals and a corresponding trend of less active (even noble) to highly active nonmetals.


 * As I understand it, and with respect, it would be more helpful to attract FAC commentators rather than co-nominator/s. I include your contributions to the nonmetal talk page in the former category.
 * --- Sandbh (talk) 00:37, 30 October 2023 (UTC)

Your draft article, Draft:Nonmetal (physics)


Hello, Sandbh. It has been over six months since you last edited the Articles for Creation submission or draft page you started, "Nonmetal".

In accordance with our policy that Wikipedia is not for the indefinite hosting of material deemed unsuitable for the encyclopedia mainspace, the draft has been nominated for deletion. If you plan on working on it further, or editing it to address the issues raised if it was declined, simply and remove the, , or  code.

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Did you get my pings?
I pinged you in Special:diff/1190384255 and special:diff/1190377110, but didn't get a confirmation message. Not sure if I was supposed to or not, but just double-checking that you were notified. YBG (talk) 03:40, 18 December 2023 (UTC)


 * Yes, I saw those pings thankls, which were two of nine. That is tricky question you asked. For context, most chemistry- or related-textbooks refer to metalloids. Beyond that we are entering uncertain territory. For sure, at least some texbooks mention metals-metalloids-nonmetals early on. After that, things become murky as to whether metalloids are (i) actually treated as a distinct category on par with the two great classes, or (ii) whether they get effectively treated as nonmetals. My impression of the literature is that, in general, the metalloids are not well treated, in comparison to metals, and nonmetals, and that it is hard to discern the actual basis for the metal-metalloid-nonmetal trichotomy, once you get into the meat of a textbook. There are, of course, some books, book chapters, or articles that do a good job of describing metalloids. Referring to "some" authors seems to be the safe option. --- Sandbh (talk) 04:45, 18 December 2023 (UTC)
 * Thanks! YBG (talk) 05:04, 18 December 2023 (UTC)
 * I asked because I didn’t get any confirmation notifications. Apparently, that is the way edit summary pings work. YBG (talk) 05:10, 18 December 2023 (UTC)

Happy New Year, Sandbh!


Happy New Year! Sandbh, Have a prosperous, productive and enjoyable New Year, and thanks for your contributions to Wikipedia.

Complex / Rational 03:55, 1 January 2024 (UTC)

Send New Year cheer by adding {{subst:Happy New Year fireworks}} to user talk pages.

Complex / Rational 03:55, 1 January 2024 (UTC)

Nomination of Discovery of the nonmetals for deletion
A discussion is taking place as to whether the article Discovery of the nonmetals is suitable for inclusion in Wikipedia according to Wikipedia's policies and guidelines or whether it should be deleted.

The article will be discussed at Articles for deletion/Discovery of the nonmetals until a consensus is reached, and anyone, including you, is welcome to contribute to the discussion. The nomination will explain the policies and guidelines which are of concern. The discussion focuses on high-quality evidence and our policies and guidelines.

Users may edit the article during the discussion, including to improve the article to address concerns raised in the discussion. However, do not remove the article-for-deletion notice from the top of the article until the discussion has finished. Boleyn (talk) 15:55, 3 January 2024 (UTC)

Your contributed article, Nonmetal (physics)


Hello, I noticed that you recently created a new page, Nonmetal (physics). First, thank you for your contribution; Wikipedia relies solely on the efforts of volunteers such as you. Unfortunately, the page you created covers a topic on which we already have a page – Nonmetal. Because of the duplication, your article has been tagged for speedy deletion. Please note that this is not a comment on you personally and we hope you will continue helping to improve Wikipedia. If the topic of the article you created is one that interests you, then perhaps you would like to help out at Nonmetal. If you have new information to add, you might want to discuss it at the article's talk page.

If you think the article you created should remain separate, you may contest the nomination by visiting the page and clicking the button labelled "Contest this speedy deletion". This will give you the opportunity to explain why you believe the page should not be deleted. However, be aware that once a page is tagged for speedy deletion, it may be deleted without delay. Please do not remove the speedy deletion tag from the page yourself, but do not hesitate to add information in line with Wikipedia's policies and guidelines. If the page is deleted, and you wish to retrieve the deleted material for future reference or improvement, then please contact the, or if you have already done so, you can place a request here. Additionally if you would like to have someone review articles you create before they go live so they are not nominated for deletion shortly after you post them, allow me to suggest the article creation process and using our search feature to find related information we already have in the encyclopedia. Try not to be discouraged. Wikipedia looks forward to your future contributions. jlwoodwa (talk) 01:53, 10 June 2024 (UTC)

Proposed deletion of Nonmetal (astrophysics)


The article Nonmetal (astrophysics) has been proposed for deletion&#32;because of the following concern: "All content is already covered in far more detail in Metallicity -- change to a redirect to that page."

While all constructive contributions to Wikipedia are appreciated, pages may be deleted for any of several reasons.

You may prevent the proposed deletion by removing the notice, but please explain why in your edit summary or on the article's talk page.

Please consider improving the page to address the issues raised. Removing will stop the proposed deletion process, but other deletion processes exist. In particular, the speedy deletion process can result in deletion without discussion, and articles for deletion allows discussion to reach consensus for deletion. Ldm1954 (talk) 19:06, 12 June 2024 (UTC)

What is Materials Science
FYI, some useful sources that may help explain the complicated history of Material Science and how/why it deliberately includes aspects of Chemistry & Physics and has subfields such as Metallurgy, Ceramics etc


 * The short encyclopedic article in


 * The history, quite detailed by Moody and Martin in


 * Early National Academies article about some of the original large scale US funding.


 * A nice overview of early days by Mori Fine (who invented the word "materials science") and Harris Marcus.

Ldm1954 (talk) 12:31, 3 July 2024 (UTC)

Concensus matters
Dear @Sandbh,

I am posting here directly as the Nonmetal/Nonmetallic materials talk pages are too congested.

Wikipedia works via concensus. I recognize that you have put a lot of work over the years into these pages, but it is still critical to accommodate other opinions. Please recognize that multiple others feel that there are other uses of the term "nonmetal" and it is not exclusive to the elements or the only use by chemists. Indeed the recent papers being discussed on the Mott parameter are by some of the most famous living chemists.

If you accommodate other opinions on this and (please) the useage in areas such as materials science then we can all move forward. I will promise to help you towards a FA, and others may as well. Ldm1954 (talk) 13:42, 15 July 2024 (UTC)


 * Thank you for your post. I happened to see it while I was checking my email. I'll ponder your thoughts and seek to provide you with a considered reply. As you say, there's some clear space to do so here. — Sandbh (talk) 13:52, 15 July 2024 (UTC)
 * I agree WP works via consensus, and strive to accommodate the opinions of other editors when these are consistent with WP policies, guidelines, and the literature. I acknowledge the existence of less common uses of the term "nonmetal". That is why the nonmetal article includes a hatnote saying:
 * "This article is about the chemical elements that are not metals. For other meanings, see Nonmetal (disambiguation)."
 * Having established the scope of the article, which is about the most frequent conception of what a nonmetal is, I feel that the first sentence of the lede should remain straightforward and focused on this scope:
 * "A nonmetal is a chemical element that mostly lacks distinctive metallic properties."
 * This approach ensures clarity for readers while respecting the article's defined scope.
 * I suggest the infrequent use of the term "nonmetal" to refer to e.g. SF6, diamond, or paraffin wax be mentioned in the Nonmetal (disambiguation) page. For convenience, I've listed below what that page could look like:
 *  Nonmetal (disambiguation) 
 * From Wikipedia, the free encyclopedia
 * Nonmetal may refer to:
 * Nonmetals in chemistry, or non-metallic elements, are chemical elements that mostly lack distinctive metallic properties.
 * Nonmetal, in astronomy, the two elements hydrogen and helium without metallicity.
 * Nonmetallic material, all materials, both elements and compounds, which are not metals; the term is used in different ways depending on context.
 * Insulating substances, e.g. sulfur hexafluoride, diamond, or paraffin wax.
 * See also
 * The entry for "Nonmetal, astronomy" is rather awkwardly worded but that is something that could be addressed separately.
 * — Sandbh (talk) 23:30, 16 July 2024 (UTC)
 * No. Multiple authors have disagreed with your statement on the meaning of nonmetal=non-metal=not a metal. You are ignoring the opinions of others, and ignoring literature that does not agree witb you. This is not how Wikipedia works. Ldm1954 (talk) 00:01, 17 July 2024 (UTC)
 * I'll first respond to the other matter re the discovery of nonmetals and Johnjbarton's revert (plus WP:BURDEN and, as you mentioned WP:ONUS) before I'll respond to your post here. Thank you. --- Sandbh (talk) 05:23, 17 July 2024 (UTC)
 * Thanks for sharing your perspective. I feel there may be some misunderstandings that we can clarify.
 * Firstly, I don't recall making a statement equating nonmetal=non-metal=not a metal. If you could provide specifics on this, it would help me understand your concern better. For instance, in our previous discussion, you mentioned, "And, of course, 'non-metal' is the same as 'nonmetal' which is also the same as 'not a metal.'" Well, no, "nonmetal" is not necessarily the same as "not a metal." Arsenic, commonly regarded as a nonmetal, is considered a metal from an electronic band structure perspective and sometimes as a full-blown metal.
 * It's important to acknowledge that there isn’t a unified popular concept of a nonmetal across all scientific disciplines. For example, a theoretical physicist colleague recently mentioned that "Astronomers, Physicists, Chemists are sitting in different bubbles. Each bubble has its own language." Philip Ball, past editor of Nature, in a Chemistry World article posted on July 11th, refers to "today’s era of siloed disciplines".
 * Given this lack of a unified conception, the term "nonmetal" most commonly refers to chemical elements that mostly lack distinctive metallic properties. I understand that there are other meanings, but these are not as prevalent.
 * Regarding the opinions of others, I strive to consider them when they align with the state of the literature and WP policies and guidelines. I believe my suggestions for acknowledging other meanings of the term "nonmetal," such as updating the disambiguation page, reflect this effort. — Sandbh (talk) 11:59, 18 July 2024 (UTC)
 * Again no. Two key points:
 * Siloed disciples is not true now and never was. Good scientists follow the science, they always have and always will.
 * You persist in stating that the term nonmetal primarily refers to elements. This has been disputed by multiple editors and is contradicted by the literature.
 * Until you acknowledge that the concensus for both the above is different from your opinion there will be no progress. Ldm1954 (talk) 12:23, 18 July 2024 (UTC)
 * To be clearer, the three terms "nonmetal", "non-metal" and "not a metal" are identical, with the associated adjectives being "nonmetallic", "not metallic" etc. Multiple texts use them interchangeably, correct grammar. There are four main uses of the words
 * Nonmetallic elements, referring to the periodic table.
 * Everything that is not a metal, the standard use in research articles and 21st century science. Definition is based upon electrical conductivity.
 * Astronomy, probably because of Kirchhoff & early solar spectroscopy.
 * Venacular, shiny stuff for cars etc.
 * If you accept these statements that comes from multiple editors and sources we can move forward. Ldm1954 (talk) 12:52, 18 July 2024 (UTC)
 * addressing your 12:23 post. Re, “Siloed disciples is not true now and never was” represents an unsubstantiated personal opinion which you are, of course, entitled to hold. That said, Wikipedia is an encyclopedia based on reliable sources, not personal views. While there are certainly many excellent scientists who cross disciplinary boundaries, the concept of siloed disciplines is still a recognised issue in many academic and scientific discussions, as per the example of Philip Ball. This isn’t to say that good scientists don't follow the science across fields, but rather that different disciplines often have their own terminologies and conventions, which can lead to varied uses of terms like "nonmetal."
 * Yes, I persist in stating that the term nonmetal most commonly refers to elements, as evidenced by multiple literature citations posted to the nonmetal talk page, here and in the Oxford Dictionary of Physics, and the Oxford Dictionary of Chemistry, as mentioned here. If multiple editors have disputed this then they have not provided evidence from the literature to back up their claims. You say my assertion has been contradicted by the literature. Could you please let me know what literature?
 * Thanks for your 12:52 post. Response to follow. — Sandbh (talk) 13:13, 18 July 2024 (UTC)
 * Addressing your 12:52 post. Thanks for clarifying your points. I acknowledge several uses of the term "nonmetal." However, it's important to note that the Wikipedia nonmetal article has already established its scope clearly with its hatnote...
 * "This article is about the chemical elements that are not metals. For other meanings, see Nonmetal (disambiguation)."
 * ...and the first sentence of the lede:
 * In the context of the periodic table a nonmetal is a chemical element that mostly lacks distinctive metallic properties.
 * This hatnote and statement are intended to define the article's focus on nonmetals within the context of chemistry.
 * Re "There are four main uses of the words
 * 1. Nonmetallic elements, referring to the periodic table.
 * 2. Everything that is not a metal, the standard use in research articles and 21st century science. Definition is based upon electrical conductivity.
 * 3. Astronomy, probably because of Kirchhoff & early solar spectroscopy.
 * 4. Venacular, shiny stuff for cars etc."
 * 1: No, the overwhelming prevalent use is the term “nonmetal”. I invite you to provide reliable evidence to the contrary.
 * 2: Please provide reliable evidence of such prevalent standard use, and that such standard use is based on electrical conductivity. By this criterion, graphite, which has a conductivity of up to 3 × 104 S•cm−1 would be a metal. See: Jenkins GM & Kawamura K 1976, Polymeric carbons—carbon fibre, glass and char, Cambridge University Press, Cambridge, p. 88.
 * 3: Agreed.
 * 4: Please provide evidence of such use in reliable sources.
 * Sandbh (talk) 14:33, 18 July 2024 (UTC)
 * You are ignoring consensus in the many, many discussions from multiple editors. I have nothing more to say. Ldm1954 (talk) 14:35, 18 July 2024 (UTC)
 * @Ldm1954: Thank you for your comment. I understand and appreciate your concerns about consensus. However, it's important to clarify that while consensus is a fundamental principle of Wikipedia, it must be grounded in adherence to Wikipedia policies and guidelines, particularly the need for reliable sources.
 * If you feel that consensus can override these foundational principles, I would respectfully suggest reconsidering this approach, as Wikipedia's integrity relies on verifiability and adherence to established guidelines. It is essential that our discussions and content are supported by reliable sources to ensure accuracy and credibility, rather than supposition, inference, misinterpretation and wishful thinking of the kind represented by your purported main uses 1, 2 and 4. I am pleased to see that we can agree on use 3.
 * I’d happy to work with you to seek to establish a position that respects both consensus and Wikipedia’s core policies, including content supported by reliable sources. — Sandbh (talk) 11:51, 20 July 2024 (UTC)
 * You are ignoring consensus in the many, many discussions from multiple editors. I have nothing more to say. Ldm1954 (talk) 14:35, 18 July 2024 (UTC)
 * @Ldm1954: Thank you for your comment. I understand and appreciate your concerns about consensus. However, it's important to clarify that while consensus is a fundamental principle of Wikipedia, it must be grounded in adherence to Wikipedia policies and guidelines, particularly the need for reliable sources.
 * If you feel that consensus can override these foundational principles, I would respectfully suggest reconsidering this approach, as Wikipedia's integrity relies on verifiability and adherence to established guidelines. It is essential that our discussions and content are supported by reliable sources to ensure accuracy and credibility, rather than supposition, inference, misinterpretation and wishful thinking of the kind represented by your purported main uses 1, 2 and 4. I am pleased to see that we can agree on use 3.
 * I’d happy to work with you to seek to establish a position that respects both consensus and Wikipedia’s core policies, including content supported by reliable sources. — Sandbh (talk) 11:51, 20 July 2024 (UTC)