Wikipedia talk:WikiProject Elements/Archive 23

Blocks
I've added several sections to block (periodic table):. The information is mostly gleaned from other WP articles with a bit of interpolation and extrapolation, so there are no external references and certainly one or more major inaccuracy. I would greatly appreciate having other sets of eyes take a look at it. Many thanks! YBG (talk) 08:54, 20 January 2016 (UTC)

When will we reach the end - of the periodic table?
An article from the Smithsonian Magazine. Note the 15LaAc (type 3) periodic table. Sandbh (talk) 05:00, 21 January 2016 (UTC)
 * Another example of using that PT structure without sourcing it. They've just copy-pasted an ill-adjusted wallchart, cramming in 32 elements in group 3. Tallying sources that make this mistake would win that argument, but not add any scientific base. Even more saillant is that you seem to see this as a proof of something.
 * Then there is this: One open question concerns lanthanum and actinium, which have less in common with the other members of their respective groups than lutetium and lawrencium. Er, "their respective groups" -- they say that La and Ac are in different groups? If, for understandings sake, we assume they mean to say "their respective category" (ie, Ln and An), this points to a different PT: they say La and Ac stand out, and so are likely to be in group 3. So they point to the group 3 = Sc/Y/La/Ac PT. -DePiep (talk) 09:08, 21 January 2016 (UTC)

Content bonanza
The new chemistry of the elements Sandbh (talk) 09:48, 12 January 2016 (UTC)
 * Intriguing cover. Being a foreigner myself to the English The Royal Society, I might need to contact their Foreign Secretary, the honourable Martyn Poliakoff (of PTOV fame), to suggest that they could replace the 1946 Seaborg PT presentation with a correct 32-column form including some modern depiction of group 3. The PT the Secretary has on its wall for 50 years might be antique by now (in PT terms that is, not in TRS terms). -DePiep (talk) 10:58, 14 January 2016 (UTC)
 * If I'm not wrong I believe the cover has a 14LaAc (type 2) periodic table. Sandbh (talk) 05:02, 21 January 2016 (UTC)
 * Touch'e. -DePiep (talk) 01:17, 9 February 2016 (UTC)

Happy 182nd, Dmitri!
Google honors Dmitri Mendeleev's 182nd birthday with a special doodle YBG (talk) 04:08, 8 February 2016 (UTC)
 * See also here YBG (talk) 04:10, 8 February 2016 (UTC)
 * It says: "the logic of his table (which reportedly came to him in a dream)". How did google find this? How to get rid of it? -DePiep (talk) 13:22, 8 February 2016 (UTC)
 * Is there any explanation on (a) the coloring used by google (did Mendeleev categorise elements like that)?, and (b) why 32 S is singled out (a pivotal element)? -DePiep (talk) 13:36, 8 February 2016 (UTC)


 * The tale of how he first dreamed of it, rather than invented it the regular way is a legend, but people fall for such things. Many know as the truth. Why wouldn't they share the fun.
 * Take it as just a thing made for people's joy, not a scientific paper. I'd have my questions if there were a point in them -- but there's none, and I am just glad they paid tribute to Mendeleev and his table and are making another small step in popularizing science. If you can't, wait for it -- and tomorrow it's gone. No biggie. :) by the way, 32 is the element weight, not the atomic number -- there was no atomic number concept in Mendeleev's best years, and Google is correct on this.--R8R (talk) 14:31, 8 February 2016 (UTC)
 * 'course. Questions same. -DePiep (talk) 15:10, 8 February 2016 (UTC)
 * Colors are aligned by columns because vertical relations between were crucial for creating the table in first place. The only thing that table could be criticized for is how K and Ca didn't get cokored as Na and Mg. Transition metals were in different groups than main group elemwnts, but the table showed only obe TM per column, so they didn't turn their PT into a Christmas tree. Remember, they were making a fun picture (why else would Mendeleev hold a cube labeled "32 S"), they are no chemists, they could pass the job exclusively to designers, they could make their mistakes.--R8R (talk) 07:24, 9 February 2016 (UTC)


 * Nice point-of-doodle indeed. But why would Google make such mistakes? These colors, I say it's huge. We should point Google to enwiki. -DePiep (talk) 01:16, 9 February 2016 (UTC)

Rethinking the list of our categories
A major visual change is coming for our PT. As such, it is a great time to either state the current categories are okay or change the set of categories.

Two possible issues coming to my head are a) combining group 1 and 2 into a single category and b) combining di- and polyatomic metals together. (Although any other issues are also worth a discussion, if there is one I haven't mentioned.--R8R (talk) 11:55, 5 January 2016 (UTC)
 * re "it is a great time to either state the current categories are okay or change the set of categories.": Redefining the (enwiki) set of categories must be kept a totally different topic from any presentation changes. They are independent topics. The graphics are e to represent the scientific facts, and nowhere the other way around. Understand that this un-tying gives a huge degree of freedom for both topics!
 * Having said this, any (scientific) redefining etc. can be developed now or in any other moment. The Graphic department should cover any scientifically well-bases outcome. Would there be a reduction of categories? Fine, we'll use or define one color less. Would a category be added? OK too, we'll add a color, systematically. Enjoy this freedom. -DePiep (talk) 10:01, 6 January 2016 (UTC)
 * Yes. I see the freedom. I perfectly realize graphics just represents science and should not affect it. The discussion would be equally valid any time, now or later; I chose now. Think of the phrase "it is a great time" as an introduction into the proposal of rethinking. There would be a different introduction if I didn't have this one, but I had it.--R8R (talk) 21:57, 6 January 2016 (UTC)
 * Indeed, can go simultaneously. It's just, no interference should occur in the development processes. -DePiep (talk) 11:31, 9 January 2016 (UTC)

Combine alkali metals and alkali earth metals into s-block metals

 * I'm not convinced about this given what you say below: the combined name is less well-known than the individual group names. Furthermore, if one were to write an article about the s-block metals, it would immediately break apart into two parts: one about group 1 and one about group 2. Double sharp (talk) 03:59, 6 January 2016 (UTC)


 * Neither am I, but since we revise our PT, I find it is best to list all possible changes and not just the ones I would easily support.--R8R (talk) 22:03, 6 January 2016 (UTC)

Combine diatomic nonmetals and polyatomic nonmetals into reactive nonmetals
I believe this would be a logical step. The set of the eleven reactive nonmetals is very diverse, that is true. However, I believe there is no use in breaking it in two (or more), because there is hardly a line all eleven could fall into either side of it. The current divide isn't one as well; one example showing that is iodine. It does fit into the C-P-Se-I diagonal trend; moreover, it is quite similar chemically to sulfur (for an element from a different group), and there is hardly a reason to keep the two apart.

Science aside, it is an even more questionable decision. One might ask, what's so different between C and Si, for example, and how does that differ from this case. The difference is in that "metalloid" is a long-established concept, and it is kept in out PT as such. "Diatomic nonmetal" and "Polyatomic nonmetal," being existing categories, are not nearly as often mentioned as a part of a standalone categorization; more often (and more obviously) they may be used as a part of a one-criterion categorization, with the criterion being structure of the substance formed by the element. All of our categories are well-known except for these two, which are "some nonmetal" and "some other nonmetal" (of other similar cases, the TMs and the PTMs clearly won't be combined, and the same is true for the TMs and the s-block metals. The s-block metals themselves are a different issue, but similarly, I only mentioned it for the sake of objectiveness, I think they should similarly be kept apart, since the individual names are better known than the collective name, and we are targeted at a wide audience), the the differing criterion being particular and not general. As it does not provide an unquestionable partition, we will be better off dropping it.--R8R (talk) 12:27, 5 January 2016 (UTC)
 * How about just hydrogen split from everything else (typical nonmetals)? Everyone treats H on its own and its chemistry (being the chemistry of a particle) is kind of sui generis. There is indeed a shift in the nonmetals from metalloid-ishness to pure nonmetallic behaviour but one can argue about where exactly it is, e.g. S and I, so that a fuzzy distinction may not be the best thing to show. Double sharp (talk) 03:59, 6 January 2016 (UTC)
 * I think it is not very accurate to say chemistry of H is "chemistry of a particle": hygrogen also has different isotopes, and essentially, it's the same chemistry. Nobody could identify heavy water as a substance completely different than water; the difference is only great for a difference between two isotopes, and does not approach a difference between the most similar elements. That means, chemistry of hydrogen is a chemistry of an element. (However, I can't yet say if I would support or oppose the idea of setting it aside.)--R8R (talk) 01:27, 7 January 2016 (UTC)
 * I think what originally convinced me though about this option (Sandbh's "Option 10" IIRC) was that the polyatomic/diatomic divide was a rather good predictor of metallicity, only falling down slightly for iodine. Then again, iodine is the heaviest halogen, so this should still not come as a surprise, whereas sulfur's incipient metallicity would come as a surprise if we focused it wholly on how close they are to the diagonal stripe of metalloids. It also falls down a little for hydrogen, which has a high ionisation energy (because the 1s electron isn't shielded) and whose negative oxidation state is unstable (because its single proton cannot fully stabilise the electron-electron repulsion forces in H−), again because it is at the extremes of its category. Maybe we should not worry so much about extremes, which are going to be slightly odd no matter how you slice them (e.g. beryllium in group 2, or group 3 in the transition metals, or hydrogen and iodine in the diatomic nonmetals). Whenever you have a category, you will have trends in it. Not everything will be homogeneous (how boring it would be if every halogen behaved the same way). Though come to think of it this is in fact an argument to have fewer categories when possible. Double sharp (talk) 04:10, 6 January 2016 (UTC)
 * I think you just basically my thinking behind the idea of keeping the nonmetals together. I could only add how a break within the nonmetals is not needed: while metals are a huge group and thus very diverse, there are clear signs of some groupings: the transition metals, for example, are obviously different than the main group metals. The nonmetals form a small diverse group without a clear division within it, and I believe we shouldn't create one in such a situation.--R8R (talk) 21:57, 6 January 2016 (UTC)
 * Intermediate points (my 2c):
 * For introduction of those two categories: /Archive 15, option 10 (August 2013. Between other issues like At halogen-or-metalloid). While I am At this: of course, the word "halogen" should not be reintroduced in the categories. As is not proposed, so OK.
 * For me as a layman, these two cats are both correct and far-fetched (iow, does not mean much for The Reader). OTOH, at this first/global encounter of a PT level, the 'nonmetal' word & class is enormously strong. It may be the first property/word a pupil will remember after seeing our PT, and even be able to locate later in a wordless PT (more than group and period, I guess).
 * As with other details, the two categories could be/should be elaborated in an article (Nonmetal).
 * I like the name 'reactive nonmetals' (exclude NGs!), from the start.
 * -DePiep (talk) 11:48, 11 January 2016 (UTC)
 * I'd like to read the opinion of on this. -DePiep (talk) 10:41, 12 January 2016 (UTC)
 * Sure. Leave it with me for a while so I can review the old history. Sandbh (talk) 10:49, 12 January 2016 (UTC)

(arbitrary break)
R8R, I see you are having a good Russian winter. There was a picture in our weekend paper of two icebreakers moving along the Moskva River, with the Kremlin in the background, during snowfall in Moscow. Apparently temperatures up there fell to as low as –20° C in the city. I hope you are rugged up.

This proposal would not result in better categorisation scheme. It would reduce the sense of wonderment associated with the current arrangement and dimish knowledge and understanding of the nonmetals.

The distinction between polyatomic and diatomic metals is easy to grasp, factually based and provides engaging insights. Briefly, the 'poly-' (Greek ‘’polys’’ = "many, much") refers to their multi-atomic molecular structures, their many allotropes, and their tendency to catenate or form compounds with multiple homoatomic links. The polyatomic nonmetals are thus 'poly-like' in at least three ways. On the sulfur and iodine question, the ability to catentate easily distinguishes the versatile chemistry of sulfur from that of iodine. Other differences in the properties of the polyatomic and diatomic nonmetals are set out in the nonmetal article.

The existence of diatomic and polyatomic nonmetals arises out of the interaction of atomic and electronic properties. Diatomic nonmetals form diatomic molecules due to either needing just one electron to attain a noble gas configuration or because they are small enough (N, O) to be able to form triple or double bonds to attain noble gas configurations. Conventional wisdom is that triple bonding is the limit for main-group elements. Since C needs four electrons to complete its octet, but is still a relatively small atom, it gets around this problem by forming three single sigma bonds and one delocalised pi bond (pi bonding being more characteristic of small atoms), resulting in graphite. The larger size of the remaining non-noble nonmetals weakens their capacity to form multiple bonds, via pi bonding, and they instead form polyatomic structures, featuring two or more single bonds, in order to achieve completed octets. So, the distinction between polyatomic and diatomic nonmetals, as well as being simple, is more fundamental than artificial.

More broadly, the taxonomic thread that runs through the three nonmetal categories is beautifully anchored in, and echoed across the remainder of the periodic table. Specifically, from left to right across an 18-column periodic table, as metallic character decreases, nonmetals adopt structures that show a gradual reduction in the numbers of nearest neighbours—three or two for the polyatomic nonmetals, through one for the diatomic nonmetals, to zero for the monatomic noble gases. A similar pattern occurs more generally, at the level of the entire periodic table, in comparing metals and nonmetals. There is a transition from metallic bonding among the metals on the left of the table through to covalent or Van der Waals (electrostatic) bonding among the nonmetals on the right of the table. Metallic bonding tends to involve close-packed centrosymmetric structures with a high number of nearest neighbours. Post-transition metals and metalloids, sandwiched between the true metals and the nonmetals, tend to have more complex structures with an intermediate number of nearest neighbours. Nonmetallic bonding, towards the right of the table, features open-packed directional (or disordered) structures with fewer or zero nearest neighbours. As noted, this steady reduction in the number of nearest neighbours, as metallic character decreases and nonmetallic character increases, is mirrored among the nonmetals, the structures of which gradually change from polyatomic, to diatomic, to monatomic.

As is the case with the major categories of metals, metalloids and nonmetals, there is some variation and overlapping of properties within and across each category of nonmetal. Among the polyatomic nonmetals, carbon, phosphorus and selenium—which border the metalloids—begin to show some metallic character. Sulfur (which borders the diatomic nonmetals), is the least metallic of the polyatomic nonmetals but even here shows some discernible metal-like character (discussed below). Of the diatomic nonmetals, iodine is the most metallic. Its number of nearest neighbours is sometimes described as 1+2 hence it is almost a polyatomic nonmetal. Within the iodine molecule, significant electronic interactions occur with the two next nearest neighbours of each atom, and these interactions give rise, in bulk iodine, to a shiny appearance and semiconducting properties. Of the monatomic nonmetals, radon is the most metallic and begins to show some cationic behaviour, which is unusual for a nonmetal.

That the terms "polyatomic" and "diatomic" will sound far fetched for the general reader is natural. This will be the case for all of our categories, with the exception of the "metal" super-category name. "Alkaline earth metal?" "Lanthanide?" "Metalloid"? What are these? I don't think this is necessarily an issue—it comes with the territory of classification science—as long as the terms are explained in more general language e.g. in the lede of each relevant article.

The html periodic table (HPT) does a fine job of categorising the nonmetals. In the literature the nonmetals are commonly explored in their vertical groups, which results in five or six "categories" depending on how boron is treated (either as a metalloid or a nonmetal). This is too many to be practical for colour category purposes and it overlooks cross-cutting patterns. Our HPT incorporates both features. It includes the named vertical groups, and the three nonmetal colour categories. Two of the latter traverse vertical groups; all three follow tangible lines of demarcation. I think the result is a "just so" mapping, with something in it for everyone: the general reader, the knowledgeable reader, and the expert reader.

In conclusion, I’m not seeing the advantages of merging polyatomic and diatomic nonmetals into a single category. Sandbh (talk) 06:37, 19 January 2016 (UTC)


 * Thank you for your concern. But have no worries: –20° is fine when you're prepared to such a temperature. A sudden fall of temperature (for example, from 10° to 0°) can be much worse than that.


 * And thank you for your detailed answer. It does a great job in providing understanding of what lies beyond the idea. And now that I've read it, I can finally formulate my main concern with the current scheme. The 11 elements in question do indeed show a great variety of their properties. But there is no universal division of these elements everyone would easily agree on. I'm certainly not advocating for such a rainbow in the upper right corner of the PT (or even its reduced state, with only the halogens standing out, which we once had). However, allotropy alone (and we only show that in the name) cannot be enough: this is not a proper overall (I can't stress this word enough) categorization; similarly, you wouldn't expect to see "BCC metals" in such a categorization.


 * But there are other differences between the two sets of the elements. I want to specify we are bound by Wiki terms, spirit, rules, etc. For that reason, I am not searching---and I'm calling for you not to---for the best table we can make; I am searching for the best table that would best fit the Wiki rules (in particular, WP:OR and/or WP:V). All categories from alkali metal to metalloid can be easily recognized as good for our purposes. Of what remains, the noble gases are commonly opposed to the rest of nonmetals in their nonreactivity, and are thus best left apart. At this point, we have the 11 elements in question. There is no divide that would fit them and be commonly found in the sources: even slicing p block into columns won't work, since a great part of it is already colored among the PTMs or the metalloids. Therefore, I believe it is best for our purposes to leave them together. One questionable category is certainly better than two. I pick a name of non-zero meaning and occurrence for that.


 * Separating four elements from a set of eleven, with no exact border between the four and the seven, which would introduce another uncertainty (sulfur/iodine), is somewhat questionable by my standards; but the worst of all is that we can't draw analogies with the other uncertainties. These ("are there 14 or 15 lanthanides?" etc.) are found throughout the sources; we have no choice but to pick one version, given the otherwise overwhelming recognizability of these categories. We now add one with an editorial decision to divide nonmetals by allotropy rather than anything. I do understand your reasoning, but the problem is, the divide has not been recognized by most other authors to be strong enough to be the divide throughout nonmetals, and thus I believe that for Wiki purposes these two problems (one more uncertainty and few RSes) are crucial.


 * Long story short: the divide may be a good idea, but it does not suit Wiki.--R8R (talk) 15:38, 26 January 2016 (UTC)

I'm still thinking about this interesting and difficult topic. In the meantime, I have some questions about your comments.


 * "But there is no universal division of these elements everyone would easily agree on." —Would it be fair to say that the nearest there is to a universal division would be "other nonmetals" (or "non-metals"); halogens; and noble gases?


 * "However, allotropy alone (and we only show that in the name)…"—Is anything more shown in "transition" metal? Or "lanthanide"?


 * "Separating four elements from a set of eleven, with no exact border between the four and the seven…" Could you elaborate what you mean by "no exact border"? Does sulfur's polyatomic structure and ability to catentate easily, for example, not sufficiently distinguish it and its versatile chemistry from that of (diatomic) iodine? Sandbh (talk) 11:31, 28 January 2016 (UTC)


 * Re other divisions: I'm not sure. I was overly confident when writing the original reply, but I have to admit I can't prove it. I'm leaning towards no, however, because in my experience, the group-by-group division is far more common (so technically yes, if it is left aside, but the gap is too wide). I'd love to do a quantitative research, if there was a way for me to figure how to perform one in a reasonable period of time.


 * "Is anything more shown..." -- both yes and no. Technically, of course, no; but in the chemical nomenclature, "transition metal" is a very basic term that denotes a set of elements that all match a single property (except the exact definition is a topic of discussion; but generally, yes. The term is so basic it cannot be more advanced than "poly-/di-/monatomic"; but unlike the latter, it has been extensively used for categorization purposes and is one of the most basic terms for that. Same for "lanthanide."


 * Of course. Both polyatomic structure and ability to catenate easily, which you mention, relate to allotropy; themselves, they are not enough in my opinion. yet on the hand, they are two elements with similar basic properties: very close electronegativities (2.58 vs. 2.66); ionization energies (compare I against S, P, and Se, and then Br: Molar ionization energies of the elements); both elements have a certain degree of metallicity, perhaps even more pronounced for iodine than for sulfur. One stronger difference is that a second electron allows for a much richer chemistry for sulfur in practical sense (sulfuric acid is well-known even for non-chemists, and a sulfur atom commonly serves as a bridge between other atoms in biochemistry, while an iodine atom is usually a terminal atom in a long molecule), but in that case, the same is true for other diatomic nonmetals---nitrogen and oxygen.--R8R (talk) 18:42, 28 January 2016 (UTC)

(another arbitrary break)
Thanks for those answers. Could you elaborate your WP:OR and/or WP:V concerns? Sandbh (talk) 10:35, 29 January 2016 (UTC)


 * What I am most afraid of is, I hadn't seen a non-Web table that puts "diatomic nonmetal" and "polyatomic nonmetal" as categories for a general classification before we adopted them in-Wiki. And a brief search in Google Books seems to show the same now, if one excludes books that are targeted at beginners at chemistry.--R8R (talk) 07:11, 30 January 2016 (UTC)

I haven't seen such a non-web table.

Some authors that come more or less close, in terms of concept or boundary lines, follow.

Fernelius and Robey (1935, p. 62) include a periodic table that divides the elements into four main classes, on the basis of crystal structure: I. The true metals (Groups 1 to 11); II. Metals with modified structures (Zn, Cd, Hg | B, Al, In, Tl | Pb); III. Elements with 8–N structures (Ga | C, Si, Ge, Sn | As, Sb, Bi | Se, Te, Po | I, …); and IV. the rest of the elements (N | O, S | H, F, Cl, Br | the noble gases). P is shown as belonging to both class III and class IV.

Wulfsberg (1987, p. 159) divides the non-noble nonmetals into "very electronegative nonmetals" (N | O | F, Cl, Br) and "electronegative nonmetals" (H | Si, Ge* | P, As,* Sb,* Bi | S, Se,* Te,* Po | I, At). [He refers elsewhere to the asterisked elements as metalloids, and to Ge, Bi and Po as "electronegative metals".]

DeKock & Gray (1989, p. 426) have a periodic table that categorises the elements into "metals only"; "intermediate structures" (B | C, Si, Ge, Sn | P, As, Sb, Bi | S, Se, Te); and "monatomic or diatomic molecules" (H | N | O |F, Cl, Br, I, At | noble gases). Just below this table there is an extract of groups 10—18 that has been disassembled into segments according to bulk coordination numbers. The segments from left to right are: metallic packing; three-dimensional networks (B | diamond, Si, Ge, gray tin); sheets or layers; tetrahedra; chains; rings; diatomic; atoms.

Birk (2005, p. 234) says in words, rather than a table: "The nonmetals typically exist as diatomic or polyatomic molecules, with the exception of the noble gases, which are monatomic. Bell and Garafalo (2005, p. 131) write, "This might be a good time to introduce the idea of diatomic elements (formulas containing a subscript greater than 2) and polyatomic elements (formulas containing a subscript greater than 2). Only seven elements are considered diatomic…and only a few are…polyatomic (such as S, P and C). Students might notice that the diatomic and polyatomic elements are located…above the stair-step line."

Silberberg (2006, p. 550) has a periodic table extract showing the structures of the representative elements. C is shown as "solid, covalent network"; P | S, Se | I as "solid, covalent molecule (diatomic or polyatomic)"; H | N | O | F, Cl as "gas, covalent molecule (diatomic or polyatomic)"; Br the same, but a liquid; and the noble gases as "single atoms"

It doesn't matter if you or I haven't been able to find a non-web periodic table using precisely this division. A periodic table is simply a graphic representation of what is written. Everything about our periodic table has been written before; it's just that no one (as far as we know) has shown it as a table. That's probably the same with many Wikipedia pages and other kinds of tables or pictures—they are mostly original, and simply draw together and represent what is said in the literature or seen in the world.

I haven't been able to find a non-web version of any of the iterations of our colour categorised table that predates when these first appeared (c. 2002) in Wikipedia. The closest I've been able to get to is in 1981 (Breck, Brown and McCowan, p. 149) and 1968 (Crawford, pp. 542–543). The Breck et al. table uses the following colour categories: metals | lanthanides and actinides | transition metals | semiconductors | life elements | halogens | noble gases. The earlier Crawford table uses black, light grey, vertical hatching, horizontal hatching, dark grey and mottled shading to distinguish: alkalis | metals | biogens | halogens | rare gases. Text labels appearing along the top and bottom-left of the table are "light metals"; "lanthanide series"; "actinide series"; "nonmetals"; and "rare gases".

After 2002 the closest non-web versions I've seen are "other nonmetal (or nonmetal) | halogen | noble-gas" type tables.

It would be a sorry day for Wikipedia if we were unable to show in tabular form what is written in the literature. But I don’t think that is what you intended to imply.

[I have not made up my mind yet. The discussion is helping.] Sandbh (talk) 05:10, 2 February 2016 (UTC)


 * Bell RL & Garofalo J (eds) 2005, Science units for grades 9-12, International Society for Technology in Education, Eugene, Oregon
 * Birk JP 2005, Chemistry, Houghton Mifflin, Boston
 * Breck WG, Brown RJC & McCowan 1981, Chemistry for science and engineering, McGraw-Hill Ryerson, Toronto
 * Crawford FH 1968, Introduction to the science of physics,, Harcourt, Brace & World, New York
 * DeKock RL & Gray HB 1989, Chemical structure & bonding", University Science Books, Mill Valley, CA
 * Fernelius WC & Robey RF 1935, ‘The nature of the metallic state’, Journal of Chemical Education, February, pp. 53–68
 * Silberberg M 2006, Chemistry: The molecular nature of matter and change, 4th ed., McGraw Hill, Boston
 * Wulfsberg G 1987, Principles of descriptive inorganic chemistry, Brooks/Cole Publishing Company, Monterey, CA


 * Hmm. I have carefully read your posting, but I have one important question regarding it. Does the following statement adequately summarize it, and if not, what's the mistake/what am I missing: "There has been a quite high number of classifications; regardless of them, it is not crucially important, because an exact categorization is not a fact that we should quote/present as widely accepted"?--R8R (talk) 12:27, 3 February 2016 (UTC)
 * I would say that the alkali metals, alkaline earth metals, Ln, An, transition metals, metalloids, halogens, and noble gases are widely accepted. And that there is no consistent treatment of the remaining metals and nonmetals. Sandbh (talk) 05:33, 5 February 2016 (UTC)


 * Thanks for the answer. I absolutely agree on each of these categories except I'll need a little time to rethink the halogens. (For example, "alkali metals" is an uncontested name for the category that includes the group 1 metals; I'm not yet sure about "halogens," because there may be other categories that include the group 17 nonmetals.)--R8R (talk) 07:27, 5 February 2016 (UTC)

S compared to I
Analysis: In its physical properties iodine is marginally(?) more metallic than sulfur whereas sulfur is appreciably more metallic in its chemical properties. Sandbh (talk) 01:44, 7 February 2016 (UTC)
 * About this post: I understand this is towards answering "do S, I belong in a non-metal category?". As such, it is a subtly different topic (i.e., off-topic): it would not redefine our set of categories. It would only change the membership lists! Other topic here may have this same deviation. Now I don't mind that much, but it might become confusing & complex at some point. By then, I might warn again ;-). -DePiep (talk) 10:54, 7 February 2016 (UTC)
 * Oh, I posted this comparison to address R8R's earlier comment in this thread about distinguishing between iodine and S. I was also wondering how iodine, which I've referred to as the most metallic of the diatomic nonmetals, compared to sulfur (which I've referred to as the least metallic of the polyatomic nonmetals). Sandbh (talk) 11:15, 7 February 2016 (UTC)
 * Sure, these things happen. But still, it expands & distracts this --already big-- topic. One could consider splitting off these OT subsubthreads into a new section. To maintain overview. -DePiep (talk) 21:04, 8 February 2016 (UTC)


 * There exist many scales of electronegativity. By the Pauling scale, SI. All-carbon persulfuranes are known, and even S(CH3)6 has been hypothesized, so there is some evidence that S is less electronegative than C (the Pauling and Allen scales state the opposite). Do you know anything about the existence of all-carbon periodinanes? Is I(CH3)3 possible? Burzuchius (talk) 12:23, 9 February 2016 (UTC)

H compared to S
Analysis: S is appreciably more metallic than H physically; H is somewhat(?) more metallic than S chemically

Combine lanthanides and actinides into one category
I think Nergaal also suggested a while ago combining the lanthanides and actinides, but I would again not support this as there is not really a clear term for what they are together because of Lu and Lr spoiling everything by being d-block elements. "Inner transition metals" would the best if that word had ever actually been well-defined. Double sharp (talk) 03:59, 6 January 2016 (UTC)
 * "Lu and Lr spoiling everything by being d-block elements" - this is from an self-wrongfooting presumption. Whether an element is in a category is not prevented by/required for its block membership. iow, categories are not limited or set by block limits. Categories are not a subdivision of blocks, they are a subdivision of the metal-metalloid-nonmetal trend. If I'm correct, the same cross-block category issue is in play wrt group 12 and He. (The same rule applies to category-vs-groups: group membership does not forbid category membership; eg At/halogen, and most main group elements). -DePiep (talk) 08:25, 7 January 2016 (UTC)
 * What this is looking for is a name for the lanthanides and actinides combined into one category. The problem is that nobody seems to agree what an "inner transition metal" is (and by the IUPAC definition, if taken literally, uranium is a transition metal as it has d electrons that are lost when forming ions, even though I don't think anyone thinks this anymore, so even the TM definition is disputable). The term is not exactly well-defined, and there is not even a IUPAC definition to help us decide which to be primary. "f-block elements" would have been an elegant solution if not for Lu and Lr being in the d-block, which spoils it. That's what I meant. Double sharp (talk) 08:55, 7 January 2016 (UTC)
 * I see. But isn't this problem created by wanting to use "ITM" for the category? That would be a redefinition of the Ln+An into a problematic definition. As you describe it, ITM is block-based (and so is what I pointed out). If we would just combine Ln and An into one category(-color) and name it "Lanthanides and actinides", no problem exists.


 * Our current table is problematic as well, so "no problem exists" is not our case, but agreed on as the smallest evil of all. Besides, is this an actual proposal to get rid of Ln and An?--R8R (talk) 10:15, 7 January 2016 (UTC)
 * "Our current table is problematic as well" - So? You mean we could swap one problem for an other? I don't understand your contribution. To me, this subtopic started with the "I think Nergaal ..." by Double sharp. -DePiep (talk) 10:45, 7 January 2016 (UTC)
 * The idea behind my post is, there is still some problem, and not no problem (re your "If we would just combine Ln and An into one category(-color) and name it 'Lanthanides and actinides', no problem exists"). This is only meant to prevent the impression the current version is problemless. No more, no less.--R8R (talk) 10:53, 7 January 2016 (UTC)
 * Yes, that's what I read. Now what or how does your statement contribute to the exploration of the issue Ds opened? I have run out of cheese. That is an other problem too. -DePiep (talk) 11:02, 7 January 2016 (UTC)
 * It's to prevent future discussion problems, not help w/ current ones. I wanted to specify that but then decided it was clear.--R8R (talk) 11:09, 7 January 2016 (UTC)


 * I collapsed this sub-thread, because I think: 1. the original point/question by is relevant (see subsection title), and 2. R8R looks off-tracking to me (but I am involved). Hope this reopens the discussion. -DePiep (talk) 22:19, 2 February 2016 (UTC)

Re collapsing the side discussion: no problem with me.

I think "inner transition metal" should not be dismissed simply because of its under-definiteness: What is "lanthanide"? (15 elements? 14, and if so, which ones?) "Transition metal"? (Sc/Y in or out? La/Ac? Lu/Lr? Zn/Cd? Hg?) A much more serious problem for me is that "lanthanide" and "actinide" are much better-known than "inner transition metals." Names are crucially important for our categorization. Most people who know the very basics of chemistry have at least heard the word "lanthanide" (or seen it in the PT hanging on the classroom wall). "Inner transition metal" is fine, I think, as a term, but much fewer people heard it before.--R8R (talk) 06:32, 3 February 2016 (UTC)


 * How come we have horizontal borders between those categories Ln/An/eka-An? are these periodic differences actaully category differences (metallic properties, ...)? Or is it just an old historic habit (because discovery-era differ)? If we group Ln+An together in one category, then eka-An is just an extension of that group. (So can have one color, be it regular or lighter for predicted elements). Time to ask in the other category section (on this page)?--DePiep (talk) 09:16, 3 February 2016 (UTC)


 * Depends on how you put it. The very term "actinide" was invented as an analogy to "lanthanide." Later elements of both categories have similar chemistry. If you ask me for non-Wiki categorization purposes, I'd, however, still keep them separated. One striking difference is that all lanthanides (except one, but for this reason it's not very important for the category, as little is known about it) are stable elements, while all actinides are radioactive (starting with thorium and uranium through short-lived transfermiums). The most characteristic actinides (the ones that we know the most about and that are most readily available) are quite different chemically from their lanthanides counterparts. For Wiki purposes, I'd absolutely object merging them.
 * Even if we combine the two, it doesn't mean superactinides will necessarily fall for that very color. The latter term also includes elements of the g-block, which are not found among the Ln or the An.--R8R (talk) 10:18, 3 February 2016 (UTC)

The extended table: get rid of the small period 9?
I have revisited the extended periodic table article. It does suggest, unlike our current extended PT, that the elements 169--172 will belong to the period 8, and not 9.

Template:Extended periodic table (by Pyykkö, 50 columns, periods 8–9)

The two major sources, Fricke and Pyykko, both suggest the differentiating electron will be 8p, not 9p. As such, I propose we follow Pyykko's representation (see Pyykko), keeping the 8p3/2 elements in period 8, even if they come after the 9p1/2 elements.--R8R (talk) 22:16, 6 January 2016 (UTC)


 * Both Fricke and Pyykko have the same results, but they differ in how the present them in a PT. What we have now is Fricke's version. The Pyykko's representation puts electronic configurations above the periodic law-themed idea of how the elements can only follow in an ascending order. I like that: I believe electronic configurations are the reason why the periodic law works in first place. As such, since we have to choose between the two, the Pyykko's version makes more sense to me (and the period 10 does not have to start with 6g elements! and they would normally be in the period 9 anyway).--R8R (talk) 22:31, 6 January 2016 (UTC)
 * Let's turn to the eka-superactinoids. Fricke's version mentions elements 173-184 in a period 10. Pyykko's version, although not in the above template, would put them in the g-block of period 9, only ending with element 190. Any thoughts on whether to include the eka-superactinoids in the extended periodic table as a question separate from whether to use Fricke's version or Pyykko's version?? Georgia guy (talk) 22:50, 6 January 2016 (UTC)


 * That is, by the way, a great question. Strictly speaking, we don't have any data for any of these elements, except for a single element, 184, and even that data, quote Fricke (1975), a major source on the element, "must be regarded as a mere speculation," even if "plausible." The data comes from an older source from 1971, and Fricke questions the whole idea of the element 184, stating, aside from obvious problems with such a high atomic number, that "no calculations of the atomic behavior were available to them [authors of the 1971 paper]." It may be a great idea to stop right after the element 172.--R8R (talk) 00:45, 7 January 2016 (UTC)
 * Fricke does not place 173–184 in his periodic table, and there is still questioning about what on earth happens after 173, so I think stopping at 172 makes sense (and killing period 10).
 * Fricke vs Pyykkö is a tough one. People have used both. I personally prefer the Fricke one because it has 139 and 140 with the superactinides (like they're expected to be), and shows that despite not having the same n, 9p1/2 and 8p3/2 are expected to behave as though they formed one p-shell. I suppose you could say that it prioritises the predicted chemistry over exactly following orbitals. Both are right in a sense, but I get the feeling it is easier to talk about Fricke because then you don't need to contortedly explain what is going on with 139 and 140, and it keeps the elements in order of increasing atomic number. Double sharp (talk) 03:03, 7 January 2016 (UTC)


 * Personally, I like Pyykko better. But we are here to explain the idea to a wider audience, and we can't just rely on personal feelings. I think Pyykko would do the job better. One thing I would definitely not miss if I saw the Fricke table but didn't know about the whole theory behind it, why are there 20 elements in the g block? I even could draw the surprising (and false) conclusion of 20 g orbitals (surely I would look deeper if I had time, but what if not). I suspect many readers would not have the question, but only because they would not pay attention to that or be indifferent. Pyykko is easy to explain: An element is located in a cell corresponding to its differentiating electron. The heavier elements, unlike the known ones, may fill the orbital in an order different to one you'd expect from the lighter elements. Relativity. This common concept, in short, does summarize all irregularities, current or future. With Fricke, you have to go case-by-case, no p block in period 8, then an extremely short period 9, then period 10 starting with the g block (but again, I insist on considering stopping after element 172). These cases would be interrelated, but different still, and either way they are obviously particular cases, and the Pyykko version implies an extendable theory.--R8R (talk) 09:50, 7 January 2016 (UTC)


 * Now one more thing: While Pyykko does explicitly present his structure as a PT continuation, Fricke, in fact, does not. Next to each horizontal row in his scheme, Fricke puts names of shells being filled and a color scheme (a pattern scheme, actually) for them and not a number of another period. Nowhere in the text is it stated that these are the actual period 8 and period 9, rather than just used in an illustration-purposed graph (which illustrates filling of different shells in each element; the eighth row already had five shells filled, so a sixth one was left out for the next row. The other rows have no more than just four shells each, so such a break may be seen as desirable).--R8R (talk) 13:30, 9 January 2016 (UTC)
 * Actually he does say it in the abstract of the 1971 paper with Greiner and Waber: "The eighth chemical period ends with Z = 164 located below Mercury. The ninth period starts with an alkaline and alkaline earth metal and ends immediately similarly to the second and third period with a noble gas at Z = 172." Double sharp (talk) 14:55, 9 January 2016 (UTC)
 * Hmm, point taken, thanks for sharing. But that still does not negate my argument re representation.--R8R (talk) 15:22, 9 January 2016 (UTC)
 * True. But does it have to be the case that 8p3/2 must appear in row 8 just because it has n = 8? After all, 3d appears in row 4, because it fills between 4s and 4p, is a valence subshell with 4s in the 3d series when it fills, and because this way it keeps the elements in order of increasing atomic number (unlike what would happen if you slotted it in row 3 after 3p, with element 21 coming before element 19). Now consider 8p3/2. It fills after 9s and 9p1/2 and is a valence subshell with these two in the 8p3/2 series when it fills. If we fill it in row 8 right under 7p3/2, then reading the table row by row, we encounter element 169 before element 165, breaking the sequence of increasing atomic numbers, that Jensen treats as a requirement of the periodic law. This seems distasteful to me. Additionally distasteful to me is the fact that Pyykkö puts elements 139 and 140 as the representatives of 8p1/2, when this subshell has been a permanent fixture in the table since element 121, and has been full since element 127, and the fact that they are so far from elements 121–138, when there is not expected to be much of a chemical difference. At this point, with 5g, bits of 6f and 7d, as well as 8p1/2 all filling together, I would simply throw in the towel and just try to follow the atomic number order and chemistry, which results in Fricke's table. Double sharp (talk) 15:40, 9 January 2016 (UTC)


 * 8p3/2 has to appear in the period 8, because for all blocks except the s block, n+l must be equal ns,p+1. this is commonly thought to be the basis for the periodic table. the s block is an exception, and the left-step table has been invented to avoid it, but it didn't hit the public. Jensen refers to a completely different issue; moreover, as a chemist and not a physicist, he may not even think about any continuation of the PT into elements 120+. "This seems distasteful to me." -- but we're not writing a music album review, we're writing an encyclopedia, this can't be a basis for any decision. As for Pyykko, he does have a reason: "For our electron book-keeping, we put the 8p* shell at E139 and E140. As seen in Table 2 for the previous element, E1385+, 6+, the available electrons will be placed in a full, 8s2 shell, the rest going to the 5g shell, and none yet to the 8p shell. This supports the present placement." The EC-twisting factor of the relativity must be taken in account. And as difficult as it is, EC is a more basic property than chemistry, and therefore it must be the basis for any table out there.--R8R (talk) 16:07, 9 January 2016 (UTC)
 * OK, what you say about n+l makes sense, but I'm not convinced about the ions argument. Consider Yb2+, which is [Xe]4f14. The outer electrons are in a filled 4f shell, and none are in the 6s shell. But that does not mean we should suddenly put 6s after 4f simply because it ionises first. Throughout the entire lanthanide series we have had 6s electrons, similarly to how throughout the entire superactinide series from element 121 we have had 8p electrons. Pyykkö himself notes the order as 5g ≤ 8p1/2, whereas he dares to put strict inequalities for the other subshells. I think all it proves is that 8p ionises first. Double sharp (talk) 16:16, 9 January 2016 (UTC)
 * Roughly speaking, this is an exceptional situation because it mixes ns and the next shell. This exception is another reason why the left-step table is such a big deal.--R8R (talk) 17:14, 9 January 2016 (UTC)
 * Yes...you make sense...
 * I suppose my only hangup left with this is that the expected chemistry is that E165 to E172 would behave like a short period 3. For example, you can see a smoothly rising trend in ionisation energies. In 3p, there is a break between p3 and p4 (the half-filled shell); by 5p the break in the trendline is still there, but now it monotonically increases; by 6p and 7p the break is at p2/p3, and we have a dip again (in 7p a huge dip that makes Fl and E118 similar in IE); and in 8p3/2+9p1/2 there is no dip at all. (This is because these two p-subshells are very similar in energy level; their electrons have almost identical eigenvalues, so the only effect – subshell splitting – is negligible.) Fricke connects the lines, so he clearly thinks it's a trend from E167 to E172.
 * So splitting them seems to obscure this relationship, and make E139 and E140 look like boron and carbon group elements when they should behave more like superactinides. Looking at Pyykkö's provided ionic electronic configurations, it looks like 8p1/2 is lost in the early superactinides until E138, and then at E139 and E140 it starts to stay in the +2 ions. But doesn't that just mean it's moving towards being a core shell that is unconcerned with chemistry? If so it still would make more sense in my opinion to account for it earlier when it is playing an active role in chemistry, rather than at its last chances of doing so.
 * I suppose the two tables have different goals. Fricke is trying to emphasise chemistry and the Z sequence while Pyykkö is trying to emphasise his calculated electron configurations. Even today you can find both used together pretty often (here's an example from Pershina). I still think it's easier to cover the chemistry in sections like E119–120; E121–155; E156–164; E165–172. Otherwise you have to jump around to explain why the trends continue through E139 and E140 and from E168 to E169. Double sharp (talk) 03:58, 10 January 2016 (UTC)
 * Yes, "the expected chemistry is that E165 to E172 would behave like a short period 3" must be the reason why Fricke chose his way. However, I, following his own words, do not think this and his whole chemistry beyond element 120, while plausible, can be taken for granted. Electronic configurations are a simpler, more basic property. As we are going into predictions with a not so great degree of certainty, I find it would make most sense to choose the one that emphasizes that simpler property.--R8R (talk) 12:56, 13 January 2016 (UTC)
 * Makes sense: I think I've turned into a Pyykkö supporter, then. Double sharp (talk) 08:26, 19 January 2016 (UTC)

sub-tread re coloring the period 8/9 p-block elements
Another question: are we sure that E167–170 are all going to be metals? If this is going to be like period 3, then maybe it would not be so. The group oxidation state being among the most important is not absolutely prohibitive – +5 and +6 are important for phosphorus and sulfur respectively too. So maybe since Fricke says that period 9 would be like period 3, we should simply copy over the classifications from period 3 (167 PTM; 168 metalloid; 169 and 170 polyatomic nonmetals; 171 diatomic nonmetal; 172 noble gas), along with huge caveats. Double sharp (talk) 03:08, 7 January 2016 (UTC)


 * Another great question in this subsection. Pyykko barely touches the issue of elements 165--172; Fricke has a little more, but even he does not go into detail regarding the similarity between his period 9 and period 3, other than mentioning the same range of oxidation states. He does not say anything other than that, and we should not try to guess what he actually meant, because a) we may guess wrong, and b) I am certain he said only as much as he could be certain about. If metallicity, for example, was similar for elements 167--172 and 13--18, he undoubtedly would add the word "metallicity" into the phrase about the similarity. Unless we have sources specifically saying these elements would be metals/nonmetals (I only have Pyykko and Fricke '75 on my hands, both being available in the Internet, and it's been a while since I last visited the topic; do we?), we should color them gray. That would most closely match the spirit of WP:V.--R8R (talk) 09:50, 7 January 2016 (UTC)

Here's my attempt at gathering every little scrap of information Fricke gives us:
 * Density: seem more suggestive of metals. However, note that Fl (a rather normal PTM) is expected to be at 14 g/cm3, some way beyond its lighter congener Pb at 11.3, so most of this is simply because of how low down these elements are on the PT and may not really have much of a bearing on their chemistry: they only increase as much as they would be expected to from density trends. This is pretty inconclusive, but suggests that this can be safely ignored as a consideration.
 * Stable oxidation states: no doubt there are some less stable states that Fricke doesn't mention, if period 9 is so close to period 3 in terms of chemical behaviour, like +4 or ±2 for element 170 or things like that. The statement of the group oxidation states being the most stable is consistent with period 3 and not period 6 (for example), but some of this is because of the inert pair effect in period 6. Now period 9 is expected to suddenly have no inert pair effect. So while this may not prevent the onset of metallization, reaching the group oxidation state would not be a problem. I could imagine 170 as a hypothetical polonium that had no trouble reaching +6. (Speaking of polonium, given the successes with longer-lived curium isotopes at higher oxidation states, I would humbly suggest trying to do chemistry on 208Po or 209Po instead of the standard 210Po. Bagnall suggested the same thing too, but to my knowledge nobody's done it because it's more difficult to work with these isotopes.)
 * First ionization energy: certainly gives the impression of the trend doing an about-turn back towards period-3 levels. But a little inconclusive; look at the huge ionisation energies of Rg and Cn, and that apparently doesn't stop them from metallising.

Now what about 171, which Fricke proudly proclaims will be a halogen similar to iodine? I think the answer lies in the fact that he specifically says iodine and not, say, chlorine. Iodine is close to the metalloid strip and has incipient metallic properties. Thus we could reasonably expect the formation H(171) and the soft base 171−, but we do not know how stable these would be. We could argue for metalloid, since the EA is within the range of variation of the known value for At; but the Goldhammer-Hertzfeld criterion would push it over the line (already it is predicted that At may act as a metal anyway, so 171 may well do so too). So maybe 171 could be simply a metal that is stable in the −1 state. We do not know how stable the 171− anion is going to be (only that it will be part of its chemistry, according to Fricke), and crucially, Fricke abstains from calling it a halogen, only similar to the halogens in the −1 state. That would be very odd if it was expected to be almost a carbon copy of iodine, so I think he is hinting that the EA does not tell the full story, because 171 is so much further down the periodic table (two more rows!).

Hence I to my surprise have come full circle to Sandbh's original position on 171; that it would be a metal with a significant chemistry in the −1 oxidation state (certainly stable enough to be reduced there by H+, but this is possible for the perhaps-even-metallic At as well). Furthermore, given 117's much lower EA and the fact that −1 is expected to be the least common part of its chemistry, I find myself to my surprise wondering if we could plausibly colour it as a post-transition metal. Fricke expects it to be semimetallic, but the fact that he uses this term makes me wonder if he means the physics definition, in which case 117 could be a semimetal and a PTM. It's not unheard of: α-Sn and Bi are like that.

My initial assignment of diatomic nonmetal to 171 was made on the basis of Fricke's first paper, which predicts chlorine-like behaviour (171− being a hard base, for example). He dials back this prediction to iodine-like behaviour in his next paper, so I think metalloid is a more reasonable description.

I think it's safest to assign them the most metallic plausible description, as it's difficult to imagine what could possibly prevent the onset of metallisation. At this high density and this far down the periodic table, the extrapolated Goldhammer-Hertzfeld criterion seems quite unable to stop the onset of metallisation for any of these elements save 172. Even in 1971, Fricke et al. refuse to call 117 and 171 halogens, only members of the halogen group (i.e. VIIA), while they do not dare to do likewise for 118 and 172 as noble gases. I think that by this point, it means that any remnants of nonmetallishness have vanished.

Now what about 118 and 172, the last two noble gases? 118 would be funny: it would be neither noble nor a gas. In 1974 Fricke dares to say that it would behave more like a "normal element", continuing the trend towards increasing reactivity down from Xe. Rn already shows cationic behaviour. The difficulty is that it would still probably be monoatomic, and so there is no way to recolour it now (there would have been if we reunified the other nonmetals into "reactive nonmetals" or "typical nonmetals", the latter excluding hydrogen). Already its fluorides would probably be ionic and non-volatile (reminds me of At and Rn), and it would be tremendously polarizable. Which means that an argument for reunifying the nonmetals would be to allow a more accurate characterisation of 118. Maybe we should change its colour!
 * Interlude: "typical nonmetal" is not ok for a category name. what are the criteria for "typicalness"? "typical" is a generic term, and it is meant to be a generic term, without any set of elements assigned to it.--R8R (talk) 15:25, 9 January 2016 (UTC)

172 would be a better noble gas, but for the fact that it would almost certainly be a solid. Fricke also calls 172 in 1974 a strong Lewis acid, so that it can donate a lone pair of electrons (and thus its IE must not be that high – in fact, the predicted value is closer to Rn than Xe). Thus fluorides and oxides are certainly possible (they are already possible in Xe). Thus we have 172 dialing back the trend towards Xe and Rn, so that we could still colour it as a noble gas. (The issue is a little moot using the current colour scheme.) Except that the category name is annoying.

BTW, I read Pyykkö and found an explanation of why he puts 165 and 166 in groups IA and IIA (not the d-block groups IB and IIB); because despite being d10s1 and d10s2, Cn2+ is expected to be d8s2 (implying 6d &lt; 7s), while 1662+ is expected to be d10s0 (implying 7d &gt; 9s). But is this not true for Zn, Cd, and Hg as well? OTOH he does neatly explain why the 7d elements are in those groups; because while 8s is inactive, 8p1/2 is not, and stands in its place! Thus 9s, which fills up at 165 and 166, is a new s-shell and a new period can start. (If not for this, I'd seriously consider a table with four extra superactinides that crams 119–172 all into period 8, that eliminates the blank spaces in Fricke's table.) Double sharp (talk) 14:28, 9 January 2016 (UTC)

P.S. Another nice tidbit from Pyykkö: it seems the current consensus is that the PT is going to end at 172 or 173. This 2011 paper explicitly says that the last element with a 1s shell outside the negative energy continuum is 173, and that this "yields the end of the periodic table". They cite Greiner on the negative energy continuum and resulting effects, but they appear to regard that anything beyond this will behave pathologically weirdly. I expect that the situation would quickly get out of hand, such that you wouldn't have your shiny new period 10 element for long enough even for the nucleons to arrange themselves into nuclear shells. They anyway expect that something will happen and that it will be prohibitive to the existence of the atom. They also give a predicted electron configuration for 173: [Usb] 9p$1 3/2$. Pyykkö also calls 165–172 the last main group elements. So I think we should cut 173–184 off our periodic table. It appears to be the consensus outside one Philip Ball article – who still admits that the exact details of what happens past 173 are unresolved (and they don't look good). Nobody's placed 173 on a PT, and judging from what I've read so far it's not sure if 173 is going to be a thing or not, but 172 will be. The limit (calculated as 173.17) is fairly close to 173. Double sharp (talk) 14:37, 9 January 2016 (UTC)


 * I will need some time to write a substantial reply, but for now, I think we can declare elements 173+ should go away. We have enough data to say that just on the basic of core Wiki rules. I'll remove them now (even though I was prepared for them with a color for the eka-transactinides.)
 * Besides, how do we attract more attention to the nonmetal discussion?--R8R (talk) 15:30, 9 January 2016 (UTC)
 * We had no difficulty with that in 2013 when it was the only thing discussed and our productivity dropped down the rabbit hole. ^_^ Seriously, I don't think it'll attract much attention until we finish with the actually active recolouring and extended PT discussions.
 * BTW, to me "eka-transactinides" is the series after the superactinides, from 156 to 172. It makes sense since the transactinides appear to be defined as elements 104 to 120 (some will include 121, if they are Sc/Y/La/Ac proponents and don't think Ac is an actinide, nor La a lanthanide), and the superactinides follow as 121 to 155. 173+ would be eka-superactinides if Fricke's half-hearted predictions were right, but this seems to be getting more and more unlikely. (In fairness he does say – though not in the words I'm about to use – that the further he gets past element 120, the more grains of salt you should take his predictions with.) Double sharp (talk) 16:20, 9 January 2016 (UTC)


 * Of course he does abstain from calling 171 a halogen. He himself said this was just a preliminary calculation. It would require a great degree of certainty to say 171 was a halogen, which he probably did not have due to limited data. So this does not tell us 171 is actually more metallic; if he with his data could draw the conclusion himself, he'd do it. Scientists are generally people passionate with acquiring new knowledge. If they could safely tell, they would. Remember the clear results on elements 119 and 120 (it is agreed these will be typical, in a wider sense, s block metals; note there is no such agreement on 117, let alone 171). 172 is okay for the label of a "noble gas," even though it's a solid: nowhere does that name require absolute accuracy, being a name, unlike a label of being just a "gas," wich is completely different in not being a part of classification, but a verifiable fact -- state of matter.
 * Throughout the time I was writing ununseptium, I was nowhere close to the conclusion it was a metal. Not because it isn't one, but because scientists must've got their data w/o classification on their minds. We call Cn a metal and Fl a metal mostly because scientists agreed to call them metals. And we, following WP:V, have to follow. I think it would be most correct (given that very pillar of Wiki, WP:V) to abstain from any declaration in situations when we ourselves can't come to an agreement, when our positions change over time. if we were a personal site, it would be OK, but we're writing an encyclopedia here, and all of our data should be as accurate and verifiable as possible. We should re-introduce gray to our extended PT until we got enough data to get rid of it for sure.--R8R (talk) 16:11, 15 January 2016 (UTC)
 * Not a bad idea at all. We would only need it for E167–171, because he explicitly states it for everything else. Double sharp (talk) 16:06, 16 January 2016 (UTC)
 * As for being a gas, I'm sure everything can be a gas if hot enough. Are there any elements that cannot be gases even at a very high temperature (write it in degrees Kelvin)?? Georgia guy (talk) 16:41, 15 January 2016 (UTC)
 * Of course not, but normally when we say "gas", we are talking about elements that are gases at standard conditions. Double sharp (talk) 16:04, 16 January 2016 (UTC)

Turn scandium, yttrium, and present lanthanides into new "rare earth metals" category
It has been proposed before, so I figure it deserves a mention. Double sharp (talk) 12:26, 11 January 2016 (UTC)
 * I posted about this at Periodic Table: Talk, here. Sandbh (talk) 09:59, 14 January 2016 (UTC)

The group 4–11 focus

 * Sandbh has expanded the topic of Talk:Periodic_table#The_group_4-11_focus. Could be overlapping with this sections. I see not problem with that yet. -DePiep (talk) 10:01, 14 January 2016 (UTC)

Move group 12 over to the post-transition metals
Exactly what the title says (perhaps even including Cn till we get the experimental evidence otherwise). Both this and the group 3 issue are related to Sandbh's topic on the group 4–11 focus. Double sharp (talk) 16:08, 16 January 2016 (UTC)


 * "(perhaps even including Cn till we get the experimental evidence otherwise)" -- why not leave as is till we get the experimental evidence otherwise?--R8R (talk) 17:11, 16 January 2016 (UTC)
 * Currently we have physical properties, but not chemical properties. The physical properties are like the lighter group 12 elements; it's the chemical properties that are expected to be different, but we don't know for sure yet. Double sharp (talk) 05:29, 17 January 2016 (UTC)
 * I have re-read copernicium. It says copernicium is agreed to be a metal and a group 12 member, and nothing else.
 * The two alternatives---group 12 belongs to the TMs or the PTMs---are equivalent; I remember one of our articles (group 12 element or maybe transition metal) once quoted a 2003 secondary research saying both are evenly distributed among authors; half the authors marked them a TMs and another half as PTMs. Given that, the two versions are equivalent, and I won't advocate for either. But the current version easily allows grouping Cn as TM, and the other one does not allow grouping as any as of now. Physical properties tell us Cn is a group 12 element. If we accept that is enough for being a TM, question solved. But if we don't, then we only know it is a metal and a group 12 member; we don't yet know if the transition is over in period 7. And if we choose this scheme, then I demand Cn can't yet belong to either category and stay uncolored. (Which I wouldn't want, so if I was to choose, I'd leave it as is.)--R8R (talk) 11:17, 17 January 2016 (UTC)
 * I am tempted to then simply leave this particular issue on hold until we finally get experimental confirmation of Cn(IV). It strikes me that the group 4–11 definition is meant primarily for the stable elements. Then we can talk about atypical compounds like the one Hg(IV) compound known. But for the superheavies, even their fleeting existence is atypical, and it is not surprising that such definitions break down. And if we are leaving group 12 in the TMs, I suppose it makes sense to leave half of group 3 there as well. Double sharp (talk) 13:15, 17 January 2016 (UTC)
 * I agree; I think I'd do just that if I was to make the decision.--R8R (talk) 13:29, 17 January 2016 (UTC)

Minor PT template things

 * Added to Infobox element: isotope ref. (eg, applied in Infobox californium).
 * Ratio: before, an isotope ref was in a "comment" line - without any preceding fact in that line (visually strange). This new param adds the ref into the subheader. Todo: check to edit all infoboxes (118+).


 * This article on extended PT uses this navbox PT in content space: a wiki-sin.
 * One effect is, a navbox never shows in mobile view, never. So I added a switch to that template, and now it does show as a regular template. Question: if you know more examples of this sin, please tell.


 * We got a complaint: in our micro-PT, the yellow category color does not distinct enough from a white main background. Especially outer H.
 * That is correct. It is with the micro-PT only, because that one does not have the element symbol letters to help, visually. Maybe I will change that color, in that micro PT only, to improve this (bold). Even before we finish the big ongoing cat-color-revaluation. (Nothing changed so far).
 * -DePiep (talk) 21:12, 20 February 2016 (UTC)

Sc|Y|Lu|Lr table spotted in popular science media program
http://www.abc.net.au/catalyst/stories/4398364.htm on battery-powered homes, at 05:05. Sandbh (talk) 11:20, 2 February 2016 (UTC)
 * Watch this. At 0:30 the Sc/Y/Lu/Lr PT. And this is great: given the omission of names for element 110 and up, the design must have been quite old as Ds was named in 2003. (The Prof spoils it by, at 1:58, showing unmoved crippled oldfashioned Sc/Y/*/** PTs more recently made by Theo Gray and ACS. Lot of work to do). -DePiep (talk) 15:14, 2 February 2016 (UTC)

Example of 32 column table by the ACS
Almost right, here. Sandbh (talk) 05:43, 2 March 2016 (UTC)
 * I followed that link and came up to a page which, after a brief introductory note, has in bold letters "Request for Nominations for the Kavli oundation Emerging Leader in Chemistry Lecturer For the 2017 Spring National Meeting in San Francisco". I can't see anything about a PT, 32 columns or otherwise. YBG (talk) 09:13, 2 March 2016 (UTC)
 * Yes, Sandbh, a nice example, and see: now their name nicely fits with the PT! I'm sure from this improvement (as promoted by Scerri), they will more easily see the light when following Scerri's current IUPAC-taskforce on the almost-thing. -DePiep (talk) 09:37, 2 March 2016 (UTC)
 * (Headslap) I see it now, in the graphic header. YBG (talk) 09:44, 2 March 2016 (UTC)
 * (... and the "almost" refers to the Sc/Y/La/Ac group 3) -DePiep (talk) 11:43, 2 March 2016 (UTC)

Happy New Year with IUPAC recognition of elements 113, 115, 117, and 118!
http://www.iupac.org/news/news-detail/article/discovery-and-assignment-of-elements-with-atomic-numbers-113-115-117-and-118.html (it's not 1 Jan yet for me, but it's already night). Double sharp (talk) 13:58, 31 December 2015 (UTC)
 * (RIKEN got 113; Dubna/Livermore got the others.) Double sharp (talk) 14:05, 31 December 2015 (UTC)
 * (Oh, and here is the 2013 article that criticised the IUPAC recommendation that -ium should be the ending for all elements, even those in group 17 or 18, which is why IUPAC proposes to amend it. I'm not too happy about naming elements based on chemical properties that are not even known, but I can't and won't argue with whatever they decide.) Double sharp (talk) 14:08, 31 December 2015 (UTC)
 * A marvelous quotation that should find an honored place somewhere in our series of articles:
 * The chemistry community is eager to see its most cherished table finally being completed down to the seventh row.
 * YBG (talk) 06:20, 1 January 2016 (UTC)

Side notes

 * I remember Scerri said the same some years ago. Too early ;-) ? -DePiep (talk) 16:57, 1 January 2016 (UTC)


 * ... and about the undiscovered elements. A bit strange that we don't have to change our graphs and infoboxes now that those elements are formally "discovered". I mean, element 119 does not state "not discovered" (except in text). Of course most of their properties are marked "predicted" OK, but the element it self not. -DePiep (talk) 16:57, 1 January 2016 (UTC)
 * Good one. On the top of my head I can suggest simply add to History, "Discovery date: n/a." Possibly an even better idea would be to state the element is not yet discovered in the very header of the template, or right after the pronunciation. ("General properties," come to think of that, could use a renaming to more closely reflect it's just about the name.)--R8R (talk) 02:22, 5 January 2016 (UTC)
 * Or state something like "This element is predicted only", for the whole? -DePiep (talk) 12:38, 7 January 2016 (UTC)
 * I think a great idea would be to add a small "(predicted)" to the header of the infobox. So instead of
 * Ununennium, 119Uue
 * use
 * Ununennium, 119Uue (predicted)
 * Thanks for the idea. I've had smth. like that in mind, but couldn't formulate.--R8R (talk) 12:51, 7 January 2016 (UTC)
 * But "Element 119" is not 'predicted' like a property, right? It just not created.
 * btw, we in the periodic tables we could just add brackets like (Uut) and (113). -DePiep (talk) 08:21, 8 January 2016 (UTC)
 * the name is not predicted, but the whole concept of element 119 is.--R8R (talk) 15:19, 9 January 2016 (UTC)

Quarkonium News from Eric Scerri
 * Great. Interestingly, he does not mention the third step in producing the Left Step PT: shift the s-block up one period (row). And exactly that is why elements 119, 120 appear in the seventh period - the point he makes. Maybe he should have consulted enwiki ;-).
 * Second: Separate topic, moved to Talk:Periodic table -DePiep (talk) 08:33, 8 January 2016 (UTC)


 * Happy extension with these four elements! (I forgot to celebrate in time ...). Four in one day!! -DePiep (talk) 19:45, 5 February 2016 (UTC)
 * Interesting (do not archive yet ;-)). -DePiep (talk) 00:35, 6 March 2016 (UTC)

Blocks in sidebar
Regarding Sidebar periodic table, after changed it to: • Periodic table blocks s, p, d, f, ...   Atomic orbitals ·  Aufbau principle I restored the extra level of 'indentation', changing it back to: • Periodic table blocks s, p, d, f, ...   (Atomic orbitals ·  Aufbau principle) My idea here was to use the parentheses provided by the extra level of indentation to contrast the PT blocks entries with the PT periods (whose subsidiary items are the periods) and PT groups entries (whose subsidiary entries are the groups). Since the subsidiary items under PT blocks are not the blocks (which are currently just redirects to the same general page), I thought it best to somehow visually indicate this difference. I did a similar thing to contrast the Metalloid section, where "(dividing metals & nonmetals)" is a completely different sort of subsidiary from the Metals and Nonmetals sections, where the subsidiaries are the subcategories of metals and nonmetals respectively. I hope this explains the thought process behind why I had the extra level of 'indentation'. If my explanation is not clear, let me know and I'll try again. If my explanation is clear but you still disagree, let's let's discuss it here first, per WP:BRD. YBG (talk) 22:05, 16 February 2016 (UTC)
 * Go ahead (in past tense). My reasoning: it is not good design to skip one level of indention. In this case: the parent of the bracketed text is not present. I need to browse WP:MOSLIST, WP:MOSTABLE, WP:NAV for more background on this. Anyway, I'll propose via /sandbox next time.
 * Another thing that's puzzling me: a lot of list-depths are used: ellipses at eol, ellipses at sol, subheader, bullet (aligned LH), central plaintext list, central bracketed list, ... Somehow this could be/should be simpler and clearer. -DePiep (talk) 10:48, 17 February 2016 (UTC)
 * Let me explain my thoughts: re ellipses at end of line at level N followed by ellipses at start of line at level N+1 are used to show connection. I chose this structure because I thought it was cleaner:
 * Sets of elements named ...
 * ... by periodic table structure
 * ... by metallic trend
 * ... by other characteristics
 * It is meant to be equivalent to this which at the time I laid it all out seemed less clean:
 * Sets of elements:
 * Sets of elements named by periodic table structure
 * Sets of elements named by metallic trend
 * Sets of elements named by other characteristics
 * I tried my hand at eliminating the bullets and ellipses and though it has promise, I self-reverted to allow discussion. You can see my attempt at special:permalink/705419656. YBG (talk) 11:30, 17 February 2016 (UTC)
 * Sure I can see what it tries to say, but hey I'm a local here, and I love studying such things. But we are not The Reader ;-). Maybe we need like this: three deep max, and one form for all (eg not mixing up bullets and ellipses). Sorry, don't have time to build demos now. It's a wonderful box! -DePiep (talk) 20:43, 17 February 2016 (UTC)

More re Sidebar periodic table
 * In Sidebar periodic table/sandbox, I have made some changes., I can explain everything (or my lawyer will), but I prefer spending writing time on your questions. For sure, it does not collapse in its home page. -DePiep (talk) 00:43, 6 March 2016 (UTC)

Missing physical properties for rare but technically important light isotopes: e.g., ²H and ³He
Having browsed Infobox element and  Infobox isotope, it is not obvious to me how to gracefully include the many physical properties of the light, rare but stable, and technically important isotopes such as 2H and 3He, which differ substantially from those presently provided by Infobox element for the natural mixture dominated by another stable isotope. This information seems to be missing from deuterium and helium-3, and hence from WP. I would welcome suggestions about how to incorporate this missing information, which amounts to more than half of the entries in each Infobox element. Thanks. Layzeeboi (talk) 22:38, 14 March 2016 (UTC)
 * I have a few of the H isotopes at User:Double sharp/Hydrogen from Greenwood and Earnshaw. It seems to me that it could be accomplished by using the element infobox in the important isotopes articles, right? (I think that'd just be D, T, 3He.) Double sharp (talk) 06:36, 15 March 2016 (UTC)
 * I agree, and your data table seems like a good start. For other physical properties of the hydrogen isotopes, I know of only this golden oldie from 1973

https://ia601605.us.archive.org/32/items/surveyofproperti641rode/surveyofproperti641rode.pdf


 * and also

Cryogens and their properties RL Mills, FJ Edeskuty - in Liquid Cryogens, Vol. 2? Vol. 2: ISBN-10: 0849357284  ISBN-13: 978-0849357282   Publisher: Boca Raton: CRC (1983) Vol. 1 is ISBN-10: 0849357276  ISBN-13: 978-0849357275   (Vol. 2 is $12 from Ama20n)

ESTIMATED D,-DT-T PHASE DIAGRAM IN THE THREE-PHASE REGION (1975) http://www.iaea.org/inis/collection/NCLCollectionStore/_Public/07/234/7234944.pdf


 * I expect to receive a reference book on ³He in a couple weeks. Layzeeboi (talk) 21:57, 15 March 2016 (UTC)


 * And NIST should be the most authoritative source for some of this info:

http://webbook.nist.gov/chemistry/fluid/
 * Also, I wonder if we should include viscosity and surface tension when available. Layzeeboi (talk) 22:28, 15 March 2016 (UTC)


 * Some properties differ for the two spin isomers of hydrogen: "If orthohydrogen is not removed from rapidly-liquified hydrogen, without a catalyst, the heat released during its decay [to parahydrogen] can boil off as much as 50% of the original liquid." So there may be uncertainty whether quoted properties of the liquid or solid really correspond to the equilibrium composition at the quoted temperature, as equilibrium is reached only after a long time in the absence of a catalyst.  The Hydrogen infobox should probably note that it (hopefully) presents the values for the equilibrium mixture.  The article Spin isomers of hydrogen could contain a table comparing those properties of the two isomers not already appearing in figures there.
 * Note that that the above NIST web site provides information on both "normal' hydrogen and parahydrogen. Also this might help:

http://onlinelibrary.wiley.com/doi/10.1002/0471238961.0825041803262116.a01.pub2/abstract DOI = 10.1002/0471238961.0825041803262116.a01.pub2
 * Layzeeboi (talk) 23:46, 15 March 2016 (UTC)

Strontium-89
The article is not new but needs alook from a person with more experience on isotope articles. --Stone (talk) 22:08, 28 March 2016 (UTC)

Category Color Set review

 * For earlier discussions about categories & background color: see /archive_22

The current set of Category legend colors we use in periodic tables at this wiki (enwiki) has some serious flaws, especially with regard to good webpage design. For example, background colors may have too little contrast with regular font color (like the red (alkaline metals) in group 1).

This topic is opened to review and improve the set. Starting point is the set as defined and used, labeled the 2015 category color set. This set is used throughout the enwiki consistently in all periodic table graphs (dozens).

Category is the name used on enwiki for these groupings (classes). There is no distinctive word for it (sometime "series" is used, but that can also refer to other classifications of elements). The definitions and compositions of the categories themselves is a scientific topic, and is not up for discussion here. There is no overall setup for this discussion. Section structure is our friend. -DePiep (talk) 12:40, 9 January 2016 (UTC)

Known issues
 * Contrast bg - font (including colroed fonts)
 * Distinction between category cellcolors (category border)
 * Contrast with background (eg yellow on white), esp in micro pt (no celltext)
 * Predicted category property (eg E119): no related color available
 * Add option ENGVAR (color/colour) in legends (not re Al, Cs etc).
 * (don't archive edit) -DePiep (talk) 20:46, 11 March 2016 (UTC)

Useful links

 * Note to all: added option to preview mobile view on your desktop. Recommended! -DePiep (talk) 10:19, 10 January 2016 (UTC)


 * WP:ACCESSABILITY -- contrast, colorblindness
 * Help:Using colors -- hue demos, HSV demos
 * 2015 category color set
 * ColorBrewer 'color advice for cartography'
 * Defines types of legend/classification: sequential/diverging/qualitative


 * Preview mobile view in desktop screen:
 * Option 1: Preferences, Gadgets (bottom section "tests & development": select "Mobile sidebar preview - Show page in mobile view while browsing the desktop site". (will add a tab; displays in smartphone screen size, vertical)
 * Option 2: In the very bottom of every wikipage: click "mobile view" link. (uses full screen width)


 * todo: contrast checkings
 * todo: color blindness checkings

Potential considerations in color selection
This is a brainstorm of potential principles or considerations. Others are welcome to add more. Ideally, items should be stated in such a way that people can vote them up or down. However, our goal at this point should be to collect as many different principles as possible, without taking the time to judge them or comment on them at this point. There is no need to sign individual suggestions -- adding an item to this list doesn't mean that you agree with it -- in fact, you may actually disagree with it. Consequently, there is no need to sign individual additions to this list.

Please do not comment on the merits of the items in this list at this point. Let us delay that discussion until we can all agree that this list is complete and includes all possible considerations - or at least all of them that we can think of at that point. YBG (talk) 05:20, 4 January 2016 (UTC)


 * Colors should be selected to provide adequate contrast with the font color
 * The palate should be selected to minimize changes from the current palate
 * The palate should be selected without regard to the current palate
 * The palate should provide adequate contrast between all pairs of colors
 * The palate should provide contrast between colors that appear adjacent in the PT
 * The palate should not over-emphasize any one part of the color spectrum
 * The palate should consider the mnemonics associations of colors where possible
 * The palate should not consider any cultural meanings of colors
 * The (non)metal color should be chromatically similar to the colors of the constituent categories
 * The (non)metal color should chromatically contrast with the colors of the constutuent categories
 * The (non)metal color should be totally independent of the colors of the constituent categories
 * The (non)metal color should not be considered in this discussion
 * The palate should ignore all existing associations, knowledge, current situation
 * The palate should consider the internal and external relations (of the categories being colored)
 * The palate should be selected using professional guidelines in coloring
 * Single step only: Let decide from memory what his highschool wallsize periodic table colors were and use those. After that Sandbh will find so-called sourcing and convince all others that they can not read a graph (it worked with group 3 descriptions, recently).
 * LOL! That's a good 'un! Seriously, I can only remember monochrome or duo-tone tables in those days. The first fancy table I saw was the two-sided Sargent-Welch version that used to be bound into the Journal of Chemical Education, once a year. Sandbh (talk) 10:40, 5 January 2016 (UTC)
 * Don't let lack of sources stop you. You'll find a way to push it. -DePiep (talk) 18:29, 7 January 2016 (UTC)

R8R's color choice principles
While all of these were not a part of the initial design specification, these are the principles I have discovered while doing the work. Feel free to agree/disagree on each.

--R8R (talk) 13:12, 5 January 2016 (UTC)
 * The TMs and the f-block categories can't be shades of the same color. They total for 68 cells of the 118 we have (fewer still if we exclude, for example, the gray ones, which are meant to stand out), and if they were one color, it would dominate the table, which is one of the reasons we consider a recoloring. One the other hand, it can't be too different as that would look not very pleasing aesthetically (so we can't have green TMs, red lanthanides, and brown actinides).
 * More obviously, the colors of Ln and An should be shades of one color, but these shades should differ significantly enough to make them impossible to mix up.
 * The hottest/warmest colors found in the table should be found in the p block, as that's the place with the most diverse and intense chemistry.
 * Yellow is a great choice for the metalloids. As the category is meant to be the intermediate of the p block metals and the nonmetals, the two should be completely different, with the color being between them, while being the in-between, should be independent from both PTMs and nonmetals (not too similar) and look like a natural delimiter. (So green-yellow-red is better than, for example, yellow-orange-red) This would allow using them for the metals-nonmetals table as well.
 * The color for the noble gases should be retained or a similar one should be found, as it suits the category logically and it differs the category from its neighbors, just as they are greatly differed by their chemistry.

Continuing as per more work with colors:
 * The spectral coloring idea remains a good idea for me. This has been proven to me once again by Double sharp, who at one point declared the difference between the diatomic nonmetals and the noble gases was great enough to see the difference between neighboring F and Ne, but not great enough to easily determine which one hydrogen (quite far from both) was. The spectrum allows keeping similar colors next to each other and not far away. (Hydrogen, of course, remains a problem for this, but the colors have been worked since.)
 * I have considered the idea of simply dividing the 360 degrees into equal sectors on the hue wheel, but I decided against it. The major reason is, equidistant colors don’t necessarily look equally different. The problem is especially remarkable with shades of green. 150 degrees and 180 degrees are much more similar than, say, 30 degrees and 0 degrees. For this reason, equal hue distances have been dropped in favor for manual color setting.
 * White is not used. I have tried white and decided against it. The color is too bright and it is thus attracting too much attention, compared to the pale colors for the other categories. However, it did influence me in that I’ve picked a brighter shade of gray for “unknown”.
 * While generally, saturation (s, can normally vary from 0 to 1) and value (v, can normally vary from 0 to 1) are constant throughout the table, it is completely okay for looks to slightly vary them. While normally s=0.25/0.15 (regular/predicted) and v=1.00 for most colors, some colors may vary from these fixed values by no more than two percent. Such small differences do not ruin the color balance and may possibly improve it, especially given the contrasts that may be found in the hue wheel (for example, h=180 is much brighter than h=240).
 * This scheme has a color for characterized superactinides. It is established because the scheme is supposed to serve more than just a couple of years, and in a possibly not so distant future we may get early superactinides synthesized.--R8R (talk) 14:42, 31 January 2016 (UTC)

Comments

 * "The hottest/warmest colors ..." No, that is an undesired cultural meaning which does not hold. Also, other colors do not have a similar 'related' meaning which makes the selection unbalanced in this. -DePiep (talk) 18:13, 7 January 2016 (UTC)
 * Same for "suits the [NG] category logically". -DePiep (talk) 19:14, 7 January 2016 (UTC)


 * Expressed by HSV, current proposed colors differ by both Hue and Saturation (and even Value once). That explains why it looks like a chaotic carnival of colors coming in from every direction. Also, it is not web-professional design. -DePiep (talk) 19:14, 7 January 2016 (UTC)
 * If I call this "different color, same tone", some good examples are in this list and this. (However, for other reasons they are bad colors: should be gradients in both cases). -DePiep (talk) 19:51, 7 January 2016 (UTC)
 * A great tip, thanks.--R8R (talk) 03:01, 9 January 2016 (UTC)
 * So, find a HSV calculator, set S and V (eg 80, 255 for starters) and pick 11 Hues on the circle (256/11 steps ...).
 * Don't forget: first drop each and every cultural/habitual ties to colors. -DePiep (talk) 06:02, 9 January 2016 (UTC)


 * WP:ACCESS mentions ColorBrewer.com (or so), that is about color for maps. Next level of quality! -DePiep (talk) 06:02, 9 January 2016 (UTC)


 * re: unchanged spectral sequnce you say. Will see what it looks like (I liked the pair-switches or ever triple-switches). Adding superactinides: bad idea good idea, but big trouble ahead (2 Feb). They are just predictions. For after 'a couple of years' we can not know what we need. More likely the category set (now 10+1) might change (merge groups 1 and 2; merge non-reactive nonmetals) quite more likely. Remember, we already agreed (did we?) that predicted categories should have the lighter shade. Most problematic issue with this is that 10 colors is stretching the limit already too much. Occupying colors for a prediction is reducing the overall effect. I can agree to pick colors on the hue-cirlce not evenly, because is easily shows that the distinctive hues are not evenly spread (some colors use a lot of degrees without changin enough). -DePiep (talk) 19:17, 31 January 2016 (UTC)
 * 2nd: OK, good idea, but it gave me a bad sleep. eka-An require their own color in the main set, but that implies we need eleven category colors (plus 'unknown'=grey=okey). That is a huge requirement (even colorbrewer stops a eight). Expect we must drop other wishes, think: coloring a font red/green to show SoM, can't afford. See where this goes. -DePiep (talk) 22:00, 2 February 2016 (UTC)


 * I understand your concerns regarding the eleventh category. The main reason why I want there to be an eleventh category for the superactinides actually is, I just want the extended table to be as good as possible, and I think having a color for the category makes it look better designed. Even the legend must be good. (But then, since we have a color for that, I want it to potentially work, and not only look good in the legend.) I originally started off with 12 categories (+eka-superactinides), but that they're gone, things are easier to manage. The main concern was, the colors for predicted AEMs and superactinides should look to some extent distinguishable. I hope I got it? However, while I (of course) want them to be easily seen as different, I don't see how I could do more given the main AM and AEM colors need to be easily different, and the main AM and NG colors need to be even more easily seen as different (given they are so far away from each other), and these differences are far more important. But again, I consider my current result to be okay, given they secondary role of those. I was able to keep the colors for fonts, except both had to become a bit darker and green had to turn into blue. (Darker is not necessarily bad: I never liked that #ff0000 we had for gases, and they colors must still be clear enough.)--R8R (talk) 07:51, 3 February 2016 (UTC)


 * Also, yes, of course, if we lose one color for nonmetals (or some other one), the scheme will need to be re-adjusted, and just dropping it won't do. But it's a different kind of change: a new supeactinide is a continuation of the current category set, a change of categories means a different category set. We can (and should) prepare for the former case within the current paradigm, and we'll have the paradigm shifted in the latter case.--R8R (talk) 08:00, 3 February 2016 (UTC)
 * I don't quite follow what you write on distinguishing. IMO, we want neighboring colors to be distinguishable more easily (including NG-AM being circular/Janet), but not those that are separated. On top of this, I found this more important to have bigger differences in the p-lock, because the categories are smaller and more random (fewer elements in each and tetris-like shapes).
 * Folding those two non-metals into one: would give us colorspace we could use indeed. OTOH: if we want a set that is widely usable, this 'spare' color could be used in other wikis and outside for those who still use the 'halogen' category (they need two colors there). Anyway, as long as there are two cat's, we should deliver two colros.
 * About eka-An: a new point. How come we have horizontal borders between those categories Ln/An/eka-An? are these periodic differences actaully category differences (metallic properties, ...)? Or is it just an old historic habit (because discovery-era differ)? If we group Ln+An together in one category, then eka-An is just an extension of that group. (So can have one color, be it regular or lighter for predicted elements). Time to ask in the other category section (on this page)?
 * Minor: for SoM, you left the green font and use a blue one., Of course, that is confusing because it is close to wikilink-blue... The new red looks nicer indeed. -DePiep (talk) 09:16, 3 February 2016 (UTC)
 * In a spectral table, there are no similar separated colors (except for NG and AM. I never considered Janet... in that case, no similar separated colors at all). But again, I think that if we should fulfill as many requirements as possible, and only if that proves impossible, drop some (say, you can't color a political map of the world with a different color for each country... there are too many). I think we must try to have all colors different enough, and drop the idea only if that proves impossible. A few days after the beginning, I didn't think I'd ever have 11 colors as different as they are now. Besides, hydrogen is a problem that demonstrates the problem well. Having all colors different enough will make a better impression on the reader (including me).
 * Re nonmetal colors: if we get all reactive nonmetals combined into a single category, I think we should have no color somebody else would use in mind. Besides, we must realize there are those who we can influence (entry-level audience) and those we can't (most professional chemists). There will always be those who will just follow us, there already are. They'll adopt our categorization as well. Besides, my initial attempts to see what this would be like showed it wouldn't look great. A good-looking table is the reason why there even was a call for a change, right?
 * I'll copy your question re lanthanide-actinide distinction to the section and will answer there.
 * Unfortunately, green won't work because of color contrast problems. Liquid is found both on the top of a greenish (TM) and a red (diatomic nonmetals) background. I had no other color left. (Of course, I tried making red not only red, but I decided the black-blue-red trio works best.)--R8R (talk) 10:01, 3 February 2016 (UTC)
 * OK, easy to clarify this: 1. we will not cater a color-set for PT's that apply a different categorisation scheme. 2. Probably the eka-Ans should be added. 3. Whenever the number of categories diminishes (like folding two into one reactive nonmetals cat), we gladly will rearrange the set (even if it was chosen & implemented a day before...). Because: one color less = better separation on the hue circle (greater distances possible). -DePiep (talk) 11:24, 4 February 2016 (UTC)
 * I agree on each point.--R8R (talk) 17:53, 4 February 2016 (UTC)
 * Now this tougher point. Given the extreme 11-cat-color primary requirement (plus grey for unknown), all other requirements take a second seat. If the state-of-matter (SoM) font coloring does not fit (e.g., because is has not enough contrast with any cat-11, or because blue looks too much like wikilink-blue): then we forbid these fontcolors (they must be black or linkblue)! We won't compromise the 11-plus-grey set. Even the simple 'predicted=lighter' principle might be impossible to reach. -DePiep (talk) 16:43, 5 February 2016 (UTC)
 * Yes, but only if we have no other choice. Actually, this looks like a job a computer could solve (or prove impossible to solve), but I'm going to be short on time during coming weeks.--R8R (talk) 06:56, 9 February 2016 (UTC)

Not sure if this is the right place to put this comment, but I trust you'll excuse me if I missed finding the right place. Anyway, I recall that one of the things that is done to help with color blindness is to avoid using hue as the sole distinction, especially with certain problematic colors. This idea could be helpful to us if we used some other method of distinguishing 'known' from 'predicted'. This would free us up to use more than just hue in creating distinction. Some alternatives: I've listed all the ideas I could think of, even ones I don't think have much possibility, in hopes that it might help stimulate other out-of-the-box thinking. YBG (talk) 09:46, 12 February 2016 (UTC)
 * Completely avoid predicted categories (i.e., mark them all gray), but that is probably much too extreme.
 * Just color a portion of the cell (e.g., the background color for the atomic number) or to use a color swatch before and/or after the atomic number
 * Use the normal color but put a dagger or some other marker in the cell and have the legend include something like "† indicates predicted category" or the like.
 * Color the cell background white or gray but use the cell border color to indicate the prediction
 * re color blindness: yes, that is a trick. Especially red and green look alike for a colorblind person, so better not use them both. re predicted categories: I proposed to put that topic in second priority, because we first must find eleven good colors for the main job. Note that the issue you mention also occurs in the existing categories (so far). So, if we have deducted 11 good colors for the categories, we can start about predictions & their added issues. (btw, colorbrewer is a good further reading on map coloring. Introduces three different tasks for coloring (sequential, diverging, qualitative). They do not use red and green together in any option set; but hey they don't have to solve the 11-color problem eather ;-). Today, our proposal separates red and green by the yellow (metalliods).) -DePiep (talk) 10:03, 12 February 2016 (UTC)
 * My point is to provide more flexibility for selecting 11 colors by completely removing the idea -- whether overt or just in the back of the mind -- that the colors must be selected in such a way that each one can have a lighter analog for the predicted colors. YBG (talk) 10:13, 12 February 2016 (UTC)
 * Agree, and for the same reason. -DePiep (talk) 10:55, 12 February 2016 (UTC)
 * Great! I presume that everyone is doing their best to take full advantage of all color parameters and not (even subconsciously) reserving some degree of freedom for potential use for the predicted dimension. YBG (talk) 07:16, 13 February 2016 (UTC)

DePiep's color principles

 * See User:DePiep/pt-2016 (in mobile view)
 * Current color set: DePiep-4: Swapped color-pairs (swapped the two greens etcs): contrast in p-block! Hues taken from the R8R-set; ~Sequential now all incl NG. Tweaked a bit (slightly away from R8R). Use white not grey for unk.
 * 21:23, 9 January 2016 (UTC)


 * Backgrounds
 * WP:ACCESS
 * w3c contrast level (AAA)
 * Adjust limits for small font-size we might use


 * color blindness (esp red-green)
 * type of coloring (range?, quantity?, ...). consult Brewer
 * Map coloring design rules/guidelines (colorbrewer, ..)
 * Incorporate properties of Categories
 * Other requirements may put in requirements to solve (SoM, border, unk property, ...)


 * Aims
 * Cover scientific base well & correct
 * Use web-design rules & guidelines
 * Make it international: The Wikipedia PT Category Color Set! (that's enwiki, we know ;-) ). Our color set may be fit for usage outside of enwiki. That is: in other wikis (who may not even bother thinking about this), and in the Rest of the World. That requires professional considerations (like ColorBrewer does).
 * Document it, both by science and by webdesign


 * Be explicit on limits & dont's, eg re border-element issues (example: exact list of elements in metalloids is not fixed). So far, such dispute/uncertainty/grey area we do not show in here (yet?), and so should be excluded from this (in its documentation).


 * Traps to be avoided
 * no cultural meanings
 * no historical meanings (eg 2015 colors)
 * never too loud. Always apply: lighter = better. (When working on this, one might think categories are Very Important and so deserve strong colors. They are not important. Colors should not overshout eg PT structure).
 * Don't check one situation (PT). check variants


 * Techniques
 * Use HSV not RGB color space. Know hue.
 * today: HSL (for lack of HSV calc templates)


 * Applied
 * Started with the same hue per category as set by R8R for now. Set S and L as some starting value.
 * Today 09:39, 9 January 2016 (UTC), had to use HSL instead of HSV. Requires different use (meaning of S,L)


 * Science
 * change text 'unk chem props' into 'unk' - this is about the one property only
 * Later, try elevating to three-cat colors for metal-metalloid-nonmetal


 * Color rules
 * see R8R ideas
 * periods are cyclic (Janets left step), not just standard 1-32 order
 * predicted color to be a lighter shade
 * consider: unk=white not grey
 * consider: different colors (by shade) for non-text variants (like the micro PT: darker)
 * research: trend not checkered
 * moid as border color (see brewer)


 * Restraints (requirements)
 * Trend
 * 11 categories + unk
 * M'oids as a
 * 'Predicted' property (now: a ~lighter shade of cat color)


 * Distinguishable between them (neighbor borders, cell-to-legend)
 * Contrast rules w3c re font (dflt=black, blue=wikilink 2x)
 * re State of Matter (SoM; now uses colored fonts black, red, green, grey)
 * re Occurrance (now: in cell border; uses dashing/dotting lines + blue)
 * re Redlinks (now: not present; not considered)
 * re blocks (now: no interference)
 * http://colorbrewer2.org/# guidelines
 * color-blindness tests
 * Works well with multiple size (cell size, font-size)
 * color perception (better distinguishing, lightness).
 * language & color ...


 * Degrees of freedom
 * No historical meaning of a color (& not 2015 colros)
 * No cultural meaning of a color
 * Use http://colorbrewer2.org/# classification types


 * Later, related
 * Use derived set for 3-class metal-moid-nonmetal (+unk) cats

-DePiep (talk) 09:39, 9 January 2016 (UTC)
 * Todo
 * Investigate & explore the trend-coloring (flowing hues by rainbow sequence, not checkered as was 2015 and R8R today)
 * more checks re background.
 * consult WP:COLOR poeple / or mw
 * copy/maintain steal useful principles R8R pointed out
 * Look at other wikis. Do they use 11 cats? Any effects we could consider?
 * describe category properties (from science)
 * Create help template "Explain cat color"
 * Document it for i18n: build Help, /doc, Periodic table category, automate
 * Nice -DePiep (talk) 22:52, 28 March 2016 (UTC)

DePiep color calculations (RGB and HSV/HSL)
Some early notes on color calculations. About HSV HSL color spaces (=3D definitions, as RGB is)
 * (Issue: we have no HSV-calculator templates yet, so I use the HSL color calculations everywhere; same principle).
 * 1. Colors are fed to a webpage in this RGB form: background:#AB4FF7 (that's 3 pairs of hexes: 00-FF for Red, 00-FF for Green, 00-FF for Blue. Each 00-FF is 0-255 in decimal notation). But. This form is unhelpful to tweak colors ("lighter please" - cannot do that by intuitively number changing). So we turn to HSV/HSL
 * 2. HSV colors: the Hue is the natural color (picked from the rainbow). See HELP:Using colors for bright hues. The Hue number is in a range 0-360 (when degrees), and circular. 0=360=full red.
 * S and V are the settings for brightness and lightness (of that same hue). Usually in % 0-100 each. Examples: the support header/bg colors for our main page are toned the same way (though with more extreme S,V numbers than pastel); this set (see its update changes).

This S,V workings is difficult to grasp for me to, I only play around with their settings ;-).
 * So I pick 11 hue numbers from the circle (~360/11 numeric steps initially, so hues 0, 33, 66, 99,...). AND I set a single fixed S,V pair for all (say 0.75, 0.85). This way, their tone is the same for all (the ~pastel-teinte today).
 * Per color, the H-S-V set is recalculated automatically into #RGB color number and fed to the templates ('HSV-to-RGB' in my sandbox Element-color-2016 list).
 * 3. Next: playing around with the Hues and SV's. Mostly shifting Hue numbers in the legend 11.


 * So, when we end up in the details and fine-tuning, you can refer to the hue number (mentioned in my sandbox), the lightness (SV-setting), or write "between AE and AEM bad distinction". I can relate to the 'violet' names you use, but that may change over time etc. Sure I will spend more time on all comments on this page. But sure, we have an avelache of topic roiight now (I postpone SoM font coloring, font-size effects, tough colorblind-test, b/w print effect, ...). -DePiep (talk) 09:10, 11 January 2016 (UTC)

I have written the templates for conversion from HSV to RGB: HSVtoRGB.R, HSVtoRGB.G, HSVtoRGB.B, and HSVtoHEX for getting a hexadecimal 6-digit code for a color as expressed in the RGB color space. Feel free to use them if you need to.--R8R (talk) 08:07, 3 February 2016 (UTC)

The R8R sandbox
The task is more difficult than it seems to be. I have established a sandbox, and if anyone wants to use it, please feel free. The preview table, the page with the colors. Unfortunately, you'll have to wait some time (10 minutes or possibly even more, I think) for the colors to take effect. (But then there's also the |PSD draft. The server asks for an email address to send a download link to; I could've found a simpler thing, just didn't bother to spend the time.)--R8R (talk) 01:31, 5 January 2016 (UTC)
 * User:R8R Gtrs/PT search for colors by R8R (talk)


 * I have a new coloring scheme in my sandbox, as can be seen here. All labels should be readable; all categories should be distinguishable; no color should prevail over the others. Please take a look, leave a comment, etc.--R8R (talk) 02:12, 5 January 2016 (UTC)
 * The scheme looks OK but it relies on categorising the alkali and alkaline earth metals into one category. I don't have any major objections to doing that subject to agreeing a new category name and hearing from others. At the same time I would like YBG to continue his overall approach to the recolouring question. Sandbh (talk) 11:27, 5 January 2016 (UTC)


 * It does not; but I have made the alkali metal color a little brighter still. Is the difference between the AM color and the AEM color clearly seen now?--R8R (talk) 12:40, 5 January 2016 (UTC)


 * I have reworked a few colors and now everyone's welcome to review it. I think I'll leave the table where it is for now (unless there are comments signifying problems, of course). Didn't take too much effort, but I now think it looks much better than yesterday. I am offering this as a candidate for a future color scheme, granted a decision on that will be adopted only after we reached decisions of structural questions (e.g. procedure, nonmetals, etc.)--R8R (talk) 19:19, 5 January 2016 (UTC)
 * I'm looking at the updated table on my iPad and still can't tell the difference between the AMs and the AEMs. Sandbh (talk) 21:36, 5 January 2016 (UTC)
 * Hmmm. A great idea, it didn't occur to me colors may look differently on different devices. I took my iPad, and have further lightened the AM color so now it's pink, light but not pale yet. I am tempted to learn if the difference is clear now?--R8R (talk) 21:47, 5 January 2016 (UTC)
 * The pink for group 2 is better. Now the colour for group 2 is too close to the colour for the transition metals. Also can you update the colours in the legend bar below the big table? Sandbh (talk) 01:19, 6 January 2016 (UTC)

I find this gorgeous. Thank you, R8R! Finally I can see the difference between "unknown chemical properties" and "post-transition metals". Even if the colours are hard to distinguish for some people, they can hover over the cells to get the tooltips. I love how the softer shades take up the bulk of the table, making it easier on the eye than it is now. (Although maybe there are too many greens?)

Here's a list of colours that have been taken in your scheme:

Double sharp (talk) 04:28, 6 January 2016 (UTC)
 * Alkali metals: pink
 * Alkaline earth metals: violet
 * Lanthanides: spring green
 * Actinides: green
 * Transition metals: blue
 * Post-transition metals: chartreuse
 * Metalloids: yellow
 * Polyatomic nonmetals: orange
 * Diatomic nonmetals: red
 * Noble gases: cyan
 * Yesss, grey for PTM was bad. Good riddance. For unk's, it might be OK (still a shade to pick), or we can use white for unk. To be explored. -DePiep (talk) 10:58, 9 January 2016 (UTC)
 * This colour scheme is growing on me. I like the fact that the s-block metals are pink-violet shades; the transition, inner transition and post-transition metals are green-ish shades and the metalloids, poly- and di atomics are at the other end of the spectrum. Sandbh (talk) 11:12, 6 January 2016 (UTC)

Thank you! My initial fear was that the scheme had too many blue shades, from which I tried to move, and never thought green could be a problem. We have 39 green cells now (15 Ln + 15 An + 9 PTM), and 41 blue ones (35 TM + 6 NG). So I still don't think it's a problem, is it?

Right now, I want to help me determine whether all colors in the regular PT are easily distinguishable (by the way, please give it a look now, I have a little reworked the colors for groups 1 and 2), and I can look for predicted colors after that. We practically need AM(p), AEM(p), San(p), San, Eka-San(p), TM(p), PTM(p), metalloid(p), diatomic(p), and NG(p). We already have the predicted color for the NGs, and my initial feeling is that the other colors should be easy enough to find; I already have two more shades of green for the superactinides, and if more green is undesirable, then there's also beige, which I have originally planned for the eka-San, but finding three shades of beige and/or brown is also doable. However, these predicted colors are secondary to our regular colors, so I'll finish them first.--R8R (talk) 13:49, 6 January 2016 (UTC)
 * "I want to help me ..." - No. "Looks good to me" is not the way to determine good colors. "Looks good to Sandbh" even less - by what authority? And, given the non-cooperative habit Sandbh expesed last half year (we still have to repair the damage in Periodic table, Readers are struggling as we speak), I have no confidence that Sandbh can judge and seek consensus on this at all. In this, I claim "no consensus" for what is means: change not accepted. -DePiep (talk) 07:58, 9 January 2016 (UTC)
 * Sandbh had said some time before I posted this he had difficulties with color perceiving. I have checked by color against color blindness, they are okay for the red-green blind and not for the yellow-blue blind. I'll give it a try but I don't think we can fit everyone in this case, as much as I want. back at that moment it didn't occur to me there's software for this.--R8R (talk) 10:02, 9 January 2016 (UTC)
 * Good start then, but for final tuning & correctness we need those tools and guides. I guess over at WP:COLOR or at Wikimedia there are people who shout know a lot about this (esp color perception). I am also enthousiastic about ColorBrewer.com. I saw you did not border greens & reds :-). -DePiep (talk) 11:04, 9 January 2016 (UTC)
 * The colours work for me. Looking at the current scheme and your proposed scheme, the former appears to be more subdued yet the contrast in colours seems to be better; the latter is more "loud" yet some of the colours appear (to my eyes) to have less side-by-side contrast. This is not big deal however. What do others think? A side-by-side comparison would be helpful. Sandbh (talk) 10:12, 10 January 2016 (UTC)
 * re side-by-side: sure needed in near future. For now: I've transcluded R8R's to my sandbox, crude start. A single variant set takes about >=6 dedicated templates, so it is cumbersome.
 * re impressions: I do like the new set being "different colors, same tone" (irrespective of the cat-assignings).
 * I'm not happy with the current sets being distinctive (though I proposed the spectrum-order). Esp the p-block is bad in distinguishing the tetris groups (which are less elements than TM and Ln+An). That is what we get when we want a sequence: green-yellow-orange ... In this, the 2015 does much better :-( . Also, looks different when checking smaller PT's (navbox, micro; and in mobile view). Maybe need more hybrid order: contrasting in p-block, spectral outside? Sandboxing goes on. (and not happy -yet- with Ds proposal, showing, to make NGs outstanding). -DePiep (talk) 11:17, 10 January 2016 (UTC)
 * Very interested to try the latter idea, but I don't understand it. Could you please explain it in a couple of words?--R8R (talk) 22:46, 10 January 2016 (UTC)
 * (not a reply:) Headache or improvement? In the set, I swapped color pairs (the greens, reds, purples, blues; not MOIDs not NGs). More contrast next to MOIDs. See my sandbox. -DePiep (talk) 11:58, 10 January 2016 (UTC)
 * re . In the extreme we can either use the 'spectrum' over a period: colors move as the rainbow does: blue-green-yellow-red. OR we can make it 'checkered': opposing colors next to each other (eg red-green-orange-blue-green-yellow). While we prefer (well, I do) the spectrum for various reasons, it has this drawback: neigboring colors look like each other (light green-yellow-orange). That makes them hard to distinguish. This even more in the p-block, where the color groups are small and irregular('tetris'-like areas with few elements). The -important- metalloid diagonal does not stand out, it takes another look (and good eyes) to see its border. So I did this trick: within one pair of colors (pair orange+red; pair light green/dark green) I swapped the spectral order: the darker red now borders yellow. The darker green now borders the yellow. I think this improves the neighbour-distinction, esp in the p-block where it is needed. Shown now in my sandbox. -DePiep (talk)
 * Aha, I see. The spectrum is the best idea I can think of: Two similar colors are easier to distinguish when they are close to each other. I have known that, and I experienced it a number of times when building the current spectrum table: Hydrogen is quite apart from both poly- and diatomic nonmetals, and it wasn't easy to see which one it was grouped with. I have seen a proposal of YBG's double spectrum here; sounded great, but then I realized we may run into this problem again. Given this, I think if a color sequence is not spectrum-based, it must be completely independent from it: this possibly could give more freedom than the spectral layout does. I'll, however, watch your sandbox to see if the checked spectrum may work; for now, groups 2 and 18 are indeed too similar, and I want to add the PTMs and the lanthanides currently are as well.--R8R (talk) 23:33, 13 January 2016 (UTC)

Updating the legend is possible, but I yet don't know how. I'll figure it out soon, though.--R8R (talk) 14:10, 6 January 2016 (UTC)
 * No need for "soon". Consensus first. -DePiep (talk) 11:04, 9 January 2016 (UTC)
 * I just had a look on my iPad and it looks impressive. The legend works well. There is another approach for consideration which I'll post shortly. Sandbh (talk) 21:42, 6 January 2016 (UTC)
 * Every time I click from R8R's table to the current one I feel disappointed with the current colour scheme – I was satisfied with it for a long while, but now it just feels lame and inadequate. ^_^ This is really impressive work. (We just need predicted colours!) Double sharp (talk) 13:57, 7 January 2016 (UTC)


 * Thanks again. :) I have a draft for the predicted colors, here (these are the simplest thing that could be done, the same colors with distance from white approximately halved; how does the easy way work? how many colors, if any, don't work?). The colors for San and eka-San are not meant to be the showcase colors, I have a draft for them in a PSD file in my computer. But to work these two categories, we need to decide first whether we will use eka-superactinides at all, we have a section below for that discussion. I strongly advise we don't.--R8R (talk) 14:41, 7 January 2016 (UTC)
 * And then there'll be the question of whether we should create a regular and a separate predicted color for both San and eka-San. Now we only a single color for the regulars and the predicteds, from which I want to move (element, say, 121 may be a reality, plus the legend will look better). Doable either way; but first we need to decide whether eka-San are in or out.--R8R (talk) 14:48, 7 January 2016 (UTC)


 * Funny, every time I want to leave something for a while to fix some questions before that, I almost immediately do the thing., and whoever I may forget: pls take a look at the new colors and see if they are easily distinguishable AND please visit the discussions on combining diatomic nonmetals and polyatomic nonmetals into reactive nonmetals and on visual representation of the extended periodic table, possibly start new ones if you think there may be other questions worth rethinking. It would be very helpful and appreciated. Thank you.--R8R (talk) 17:37, 7 January 2016 (UTC)

Update

 * Links: the main 18-column table, the extended table, the page with colors.

I have stuck to the general idea of spectrum coloring, improving it with small modifications, having further adjusted the colors over time, including the font colors for states of matter and the frame colors for occurrence, and I have resulted in a scheme that I consider to be a major improvement to the previous one. But now, of course, I need your comments to know if I'm right and if it's good; comments would be very welcome.

I have described the principles the scheme is built on above, where you can find both old and new principles. I've had the colors tested for contrast, for both the font/cell background contrast and the frame/cell background contrast.--R8R (talk) 07:29, 3 February 2016 (UTC)

Contrast checks (WP:Access)

 * About contrast between background and font color, and legibility (re in general & colorblindness)


 * Contrast check for red font (gases) fails. -DePiep (talk) 18:27, 7 January 2016 (UTC)
 * Fontcolors for gas, liquids, unk fail contrast check on all ( existing today's proposed) backgrounds. Taken into account that it should suit smaller fonts too. -DePiep (talk) 19:04, 7 January 2016 (UTC)
 * DePiep, what does fail mean? As I understand, you rely on the contrast ratio; what is the lower limit do you use (as there are many)?--R8R (talk) 05:13, 9 January 2016 (UTC)
 * A dumb question, nevermind--R8R (talk) 05:34, 9 January 2016 (UTC)
 * All analysers use the W3C calculation + rules. (see WP:ACCESS). Don't know the numbers. In our case, I'd say we must be better (higher border number) because our fontsizes sometimes are smaller than the default in the w3c numbers. My COlorPicker also gives ratios for colorblindness (eg red + green are bad). -DePiep (talk) 05:58, 9 January 2016 (UTC)
 * Maybe this won't solve at all (colored font for legend). We could also add a rule: 'may not be used in smaller fontsize', or even 'not colored fonts at all' and find a new way to show this. Or, why not, leave SoM out completely. -DePiep (talk) 06:07, 9 January 2016 (UTC)

Metallicity as a trend

 * Since metallishness is a trend, the colors (hues) should be shifting left-to-right. Not checkered as it is now. -DePiep (talk) 18:27, 7 January 2016 (UTC)
 * Perhaps, but it's not a great trend. There are fairly important local differences, and actually I think the slight deviations from a pure spectral scheme help ease the load of similar colours. R8R's scheme has three greens, but it works for me because they're not adjacent. If they were adjacent, it wouldn't – at least for me. Double sharp (talk) 03:36, 8 January 2016 (UTC)
 * The local differences do not invalidate a trend in this. The main point is that in a period, any run-of-single-color is not split (all category-X elements are adjacent, there is never a category-Y element embedded). Another thing to note is that the periods themselves are a trend (putting the P in PT). While being a different trend (but unrelated?) using a scattered color set breaks this aspect visually. Especially since the colors are much more intrusive than the period. To the reader is suggested that the elemetns are thrown together like dice. That is bad. To add, I can suggest that the trend can 'pivot' around the metalloids (as R8R already has introduced). In general, we should not pick colors because "they work for me". And about the 3 greens, Ds: sure you will be able to see their diff. This works even more so when they are adjacent, as Ln-An shows. -DePiep (talk) 10:19, 8 January 2016 (UTC)
 * Found a new illustration helping me. My sandbox User:DePiep/pt-2016 now uses R8R's colors as is, but in a lighter shade (shades irrelevant in this). Seeing the legend, it undeniably suggests/states that those blues have something in common for being blue (but they just are TM, NG ?!). Same for the greens (Ln, An, PTM ?!). This is undesired. -DePiep (talk) 10:58, 9 January 2016 (UTC)
 * I question my own statement that metallicity (our categories) is a trend along the period. Since we do not have an article yet about the categories (comparing), I don't know if this is true. OTOH, supporting/suggesting a trend (by following the rainbow spectrum left to right), we do strengthen the Main Trend: chemical reactiveness (Period!). I could live with this effect. Also because it makes the PT easier not wilder (chaotic/checkered) in coloring. Topic to be revisited. -DePiep (talk) 09:49, 11 January 2016 (UTC)

With regard to metallishness/metallicity and the color spectrum, it seems to me there are two ways to spread the spectrum across the PT The second means that adjacent colors are further apart in the spectrum (except for 0-1). Have I explained this enough that you can understand the general idea? If so, does it merit further thought? YBG (talk) 04:43, 12 January 2016 (UTC)
 * 1) colors  : In one series from left-to-right in the PT,
 * 2) colors  : In two series from center-to-edge in the PT,
 * Yes, I see. It is another more step away from straight spectral (restless). Minor, note that when circular (group sequence 17-18-1-2) it has 5-7-8-6. Will dive into this. -DePiep (talk) 10:21, 12 January 2016 (UTC)

Language and color recognition

 * This does depend on how your native language as a viewer breaks up colour terms, so it could make a difference on other WPs. In Chinese for example pink is treated as a variety of red and not a basic colour, so AM and diatomic nonmetals in R8R's scheme are going to be perceived as distinct shades of red rather than two separate colours. I don't think you can get around this for all languages because of those languages with very few colour terms, so if we are exporting this scheme to other Wikipedias, I think we have to admit defeat on this one and simply choose colours that can be easily distinguished – at least as different shades. It's not a vital thing like catering for colour blindnesses; we already have multiple shades of red in the current scheme, and nobody complains about it. Double sharp (talk) 13:06, 9 January 2016 (UTC)
 * Guess I don't understand this. What I tried to explain: the legend has two blues for TM, NG (R8R's, mine, ...). We assume they are distinct enough for the purpose. Al fine so far. But when I see the legend/PT, I see two blues and subconsciously conclude they are related, and less-related to the other colors. This blue=blue connection is independent of culture (language, education, habit). The same for green colors. Now when the colors jump in the period (as these examples do), that is an undesired effect. (I actually do see a 'bridge' over the nonmetals, a connection/association/relation. Also a 'bridge' across TMs for the greens. Then I go: what is the meaning of that bridge? - there is none we know).
 * If I get you right, you say that language of the viewer is in play. I don't understand. How would the name or language-association for two colors steer the eye? Would a Chinese not see the blues as two blues? -DePiep (talk) 13:19, 9 January 2016 (UTC)
 * More strongly than you'd think. Give this a read: |a short article inside--R8R (talk) 14:23, 9 January 2016 (UTC)
 * A Chinese may even see the greens as related to the blues, because 青 (qīng) can mean either colour, although since there are unambiguous words (蓝 lán for blue and 绿 lǜ for green) it may not be the case. It would be more likely with pink and red, since pink is considered in Chinese to be a shade of red, so they'd see a link between alkali metals and diatomic nonmetals. OTOH maybe R8R doesn't see the blues as two blues, but as two different colours, because IIRC in Russian light blue and dark blue are non-overlapping, different words (голубой and синий). But I'd have to ask him about that. Double sharp (talk) 14:52, 9 January 2016 (UTC)
 * In general, голубой and синий are two entirely different colors. In practice, personally, I am too used to the English blue and the German blau, so I usually think of "blue" as of some intermediate color, and even in Russian, if someone says the word синий, I may ask, "do you mean the синий синий or голубой?", if the color is particularly important for the story. But in general, yes, these are two completely different colors.--R8R (talk) 15:41, 9 January 2016 (UTC)
 * Wish you hadn't told me this... (looks like it's not just the words used like "dark" for all darks, but the cultural implication to only recognise the "darks" as such in upbringing. Impressive). -DePiep (talk) 11:30, 10 January 2016 (UTC)
 * So there is a language(/cultural) perception in colors. Now I see it is everywhere:
 * (LOL/side topics ahead): this person is perceived to have two different iris-colors (but is ithat true, or is it a cultural perception - after all, he defined a new culture himself). How did he see the PT?
 * Does this relate to this story? Currently, iu:white is not even one word!
 * Now that you mentioned this, I remember that my mother could recognise & name 50 different browns (in couture), I know only two (light and dark). -DePiep (talk) 09:40, 11 January 2016 (UTC)


 * I am happily surprised that this first throw by R8R is already gaining support. Of course, given what we come from (the 2015 colors) this could be an easy achievement, but I am also happy that the mold is broken to use "red is for alkali because fire" and "because I am used to a reddish there" -- almost completely broken. That said, the current set is not fit for mainspace because of blocking issues I mentioned throughout. -DePiep (talk) 10:25, 8 January 2016 (UTC)

I have read a number of guidelines earlier today, and I think it's been a great change with the sandbox I've made. The colors have calmed down and the color order is finally straight rainbow.


 * Now that you're in the game, I may leave it just there if you want me to. However, I'd love to mention one thing: the colors, while providing contrast with the text, can't be too pale. While (of course) intense colors are certainly not desired, too pale colors are difficult to distinguish on my first look from each other, even though I'm a person with no eyesight problems. This causes eyestrain, which is one of the reasons why there are web coloring guidelines. Good luck with finding a color contrast enough from the current diatomic red; I had to darken the current #ff0000 a little to reach even aa. I'm afraid the aaa is unreachable with the current bright red: the contrast between #ff0000 and #ffffff is 4.--R8R (talk) 13:17, 9 January 2016 (UTC)
 * My whole setup is that you'd keep running. I need my ideas tested & criticised, I'm fine with alternative sandboxes. As we have discovered here, dozens of aspects must be taken into account, so at least it is a cyclic development process. eg I plan to evaluate each of the remarks re your sandbox against my setup (and use/steal every improvement along the route).
 * What we do need is time (I am afraid we'd push an early version for the low hanging fruit, and then it stops). I only have begun reading about bordering colors & distinctive colors. And that number 11 makes this a huge challenge! All pro tools need evaluation. I want to invite webpage-designers from wikimedia.
 * Maybe you are interested in building the support to get this well-based and spread international: article Periodic table category should be blue, etc.
 * Now for today I'm off; bizzy in RL next week. -DePiep (talk) 13:52, 9 January 2016 (UTC)
 * PSs 1. I started with the extra pale colors, knowing that they only would get darker in the compromises. It's a trading trick ;-). 2. Your showing confidence in my approach is well appreciated over here -) . -DePiep (talk) 16:18, 9 January 2016 (UTC)

General comments on the R8R sandbox

 * The lanthanides and noble gases (on my iPad) now seem almost identical in colour; the transition metals and the post-transition metals are also noticeably close in their shading. Sandbh (talk) 21:32, 11 January 2016 (UTC)
 * Yes, I think they're too similar in R8R's current version.
 * What's your opinion on DePiep's sandbox? Double sharp (talk) 07:03, 12 January 2016 (UTC)
 * I like R8R's version except I would make the PTMs grey using the colour of the elements with unknown properties and colour the latter white. I think the contrast would be better that way, In the table above the colours of groups 1 and 2 are too close as are the TM and PTM colours.
 * Pls follow my sandbox, some evolution & playing in there (also re Ln/NG and TM/PTM you mention). Grey in the main sequence is breaking the setup: from hue circle; grey is not a hue, undesired. Pls note which PT's you'd like to have in a compare-testpage (expect 2 or 3 color sets in there in any PT). Somehow the AM/AEM is ending up too dark again, as in 2015 ;-).

I've been tinkering around with the colours. I think the trouble with purely going mathematically, equally spacing the hue values, is problematic as the categories of English are not equally spaced. I think yellow is a pretty clear category around 60°, but it seems like almost anything from 90°–150° can be taken for green, and thus you do not see a difference between TM and PTM even though it is bigger than between metalloids and TM, because English distinguishes the latter (yellow/green) but usually not the former (chartreuse/green). I've tried to exaggerate the differences in the pairs you mention, although it drives the noble gases into a wall. Right now I can see the difference (to me, group 2 is a bright magenta while group 18 is now a dim rose, that can be told apart from the nearby dull red), but I'm not sure if you can. Double sharp (talk) 14:38, 12 January 2016 (UTC)
 * Top table is better now. I can tell the difference between all the colours (there's not much in it between groups 2 and 18). Sandbh (talk) 22:15, 12 January 2016 (UTC)

The DePiep sandbox

 * User:DePiep/pt-2016 (mobile view) by DePiep (talk). Please do not edit; discuss here.·
 * Current color set: DePiep-4: after some playing: full spectral, (NG joining in), Hue ca 30 deg/step. Kept swaps-per-pair. Change: white for unk category, change text in legend to 'unknown' only. -DePiep (talk) 18:55, 10 January 2016 (UTC)

Is this about right(?):

Alkali metal Lavender blue Alkaline earth Lilac Lanthanide Aqua Actinide Pale blue Transition metal Light green Post transition metal Dark green Metalloid Yellow Polyatomic nonmetal Red Diatomic metal Orange Noble gas Pink Unknown White --- Sandbh (talk) 09:54, 14 January 2016 (UTC)


 * What shows badly is the fact that R8R colors differ by Saturation too, and even Value (see An green). -- 9 Jan 2015. Now R8R uses HSV-bases set (same S,V for all).  So far no objections to this approach. -DePiep (talk) 07:41, 10 January 2016 (UTC)


 * "huge swath (area) of a color" (think TM bright green). IMO solved: colors are more soft/pastel & all alike in this, so there is no bright color taking all attention any more. Removes a restraint (more freedom=OK). -DePiep (talk) 09:24, 11 January 2016 (UTC)


 * and others: what would a compare-color-sets testpage look like? Which PTs, legends, info, and how? -DePiep (talk) 09:26, 11 January 2016 (UTC)

Predicted category colors

 * Split into separate subsection

Now how does this work with predicted shades? Can we have a Fricke extended table? Double sharp (talk) 04:28, 6 January 2016 (UTC)

We practically need AM(p), AEM(p), San(p), San, Eka-San(p), TM(p), PTM(p), metalloid(p), diatomic(p), and NG(p). We already have the predicted color for the NGs, and my initial feeling is that the other colors should be easy enough to find; I already have two more shades of green for the superactinides, and if more green is undesirable, then there's also beige, which I have originally planned for the eka-San, but finding three shades of beige and/or brown is also doable. However, these predicted colors are secondary to our regular colors, so I'll finish them first.--R8R (talk) 13:49, 6 January 2016 (UTC)


 * When main set design is made (following pro guidelines), ei use hue-only choice, the 'predicted' category colors are easily and correctly derived in one systematic step: finding the one lighter shade (calculation) for all of them. Is what we did/tried in the current set, but the reds forced us to us into the strange dark red for E119). -DePiep (talk) 19:42, 7 January 2016 (UTC)

Redefine categories
Since we do the recoloring, it may be a great time to reconsider which categories we need to show. For example, the issue of combining the s block metals together has been raised before. As a personal preference, I would love to finally reunify reactive nonmetals, now divided into five diatomic and five polyatomic ones, a rare division these days, quite arbitrarily dividing a small diverse group of nonmetals into smaller groups that are still very diverse for their size!--R8R (talk) 01:57, 5 January 2016 (UTC)
 * "it may be a great time to reconsider which categories we need to show" - yes, that may be exactly what I wrote above. In fact, recoloring is useless unless this analysis is done beforehand. I also wrote we don't need a color brush now ie not a sandbox. OTOH, rediscussion the categories themselves is not required and not advisable in this. Clearly the topic is complicated enough (as in: multiple questions are in this together), which shows by multiple editors here mixing up things and even adding unrelated topics. Throwing unrelated topics into the issue is the worst thing to do, and steers towards a bad discussion. I expect from editors in science that they know how to keep unrelated issues unrelated. -DePiep (talk) 03:41, 5 January 2016 (UTC)
 * Yes, pls start a separate discussion on any proposal to reconsider which categories we need to show. Sandbh (talk) 11:32, 5 January 2016 (UTC)

Colors used elsewhere

 * Encyclopædia Britannica (1997-2010)
 * 13 graphs, heavily using category colors. No metalloid category. Legend colors do not match PT colors?!

Big bold colours
For a fresh look at a different colouring approach see here.
 * meta-synthesis.com
 * So, a bright and optimistic spectrum-based approach? (Also, no lanthanides and actinides? How naughty. They ought to be sent to bed without any supper. ^_^)
 * I think the colours are too dark. They look fine because the lettering is in white; but we, using normal black lettering, are going to have problems. Additionally, even if a spectrum is used (like R8R's), I'd prefer it not to be strict; I like how R8R splits the greens (a fairly obvious light/dark pair in the f-block is fine, but then he uses blue for the transition metals to avoid too many colliding greens, going back to chartreuse for the post-transition metals). Furthermore, I would argue that the noble gases ought not to continue the trend from either the right or the left. As one goes further towards the edges of the periodic table, the trend is towards increasing reactivity, a trend that is abruptly cut off with the noble gases. Given that these trends are not uniform throughout the periodic table, I think R8R's deviations from a pure spectral scheme make his scheme better. Double sharp (talk) 08:10, 7 January 2016 (UTC)
 * Agree with your opening lines. Disagree on the spectrum thing: needs spectrum for being a trend. "I like the greens separated" is not a coorect way to handle this. Professional web design, esp in geographic maps & region properties, can help us better. -DePiep (talk) 10:30, 8 January 2016 (UTC)

Outside of chemistry
Good mapping examples from elsewhere:
 * Now that the US election circus is touring, there are great infographics around. The NYT is famous, and one can check this one, just for inspiration: fivethirtyeight.
 * Note that later in the process, the number of colors (candidates) will be lower, so better take a look asap. -DePiep (talk) 21:24, 11 February 2016 (UTC)

What about white?
Is there no use for a white colour category? White is a colour too. Sandbh 09:59, 10 January 2016 (UTC)
 * Only when useful. However, just like greys and black (and brown, for some reason I don't know yet), it is not a hue, not a point in the rainbow. As such, it would be an exceptional color in the spread we want. So far, I only thought of using white for the unk 'category'. Must also take care of merging-with-tablebackground effect. (lol: and then add a "unk (predicted)" category?).
 * btw, greys, including a very light shade, are used as support colors: table title, background, box borders, column/group stressers. White, as a sort of grey, is associated with that. -DePiep (talk) 10:08, 10 January 2016 (UTC)

Actually, I think there is a use for a colour that merges with the table background. For quite a while (four years from 2006 to 2010 IIRC), element 117 was not discovered (though everything else in the first 7 periods was), and so it had no border, being simply undiscovered. I would argue that in such a case (which could happen today if, say, element 120 was discovered before element 119), the cell concerned should appear, but it should receive a blank background, defined in the legend as "undiscovered". It shouldn't have a border for the same reason. (We'd have this today for elements 119 and 120 if we magically all converted to left-step tables.)

Incidentally, while we're on the subject of how to handle discoveries of future elements, I think that when E119 and E120 are discovered, we can simply take the old table and add them in their places below Fr and Ra (8s). The addition of the superactinides will royally mess up all the 18-column tables, so that will be our grand opportunity to turn 32-column once and for all (since reliable sources are not going to have a choice). At that point, I'm not sure how much to show. It seems odd to have only elements till 122 discovered, for example, and show 50 more blank-background elements. So maybe we would only show up to the highest number we know (filling in only gaps), or maybe we would show up to the end of the series (thus 155, then 164, then 172). But we can worry about it once the first superactinide is discovered. Double sharp (talk) 14:26, 10 January 2016 (UTC)
 * This is about category colors first now, the cell background. Not other properties (SoM is handled elsewhere). I already changed in my sandbox the legend text to simple "unknown" from earlier "unk chem properties" (plural even!). Here it means: "the category is unknown", nothing about other properties let alone discovery. SoM unknown is handled elsewhere.
 * Undiscovered elements (119+): don't see a issue wrt the categories. 119 or 120 will be unk category first, and so be have the bg as 118 in this. Or a predicted category - fine, we can deal with that too. Occurrence (border) and SoM will a\rfe available too. Indeed, the only thing missing is a note for "undiscovered"
 * Use white intentionally: I don't favor now. We should say 'don't know' just as clearly as the others. Thats different from saying  (nothing).
 * Into Janet left steps: I don't mind, great. I am keeping an eye on that the colors work in all those variants. For example, later we'll have to check if group 1 can be next to 18 re the colors. This is part of the general philosophy of the PT (as Janet uses correctly). 2015 colors do too.
 * White category: Now I also sandboxing the white color for this cat. Just experimenting. Still the issue could be the merge with table bg (no cell square visible); Even fatal in the micro PT which has no text/symbol at all. Maybe a grey would be better.
 * Together, these are 'constraints' we try to fulfill with the new set (each one is tying us further ..). If some can not be achieved, we'll have to compromise.


 * TL,DR;
 * White for "category unknown" tested in sandbox. But invisible cat color would be confusing imo. Might need differentiation from general whitish background. Unknown elements 119+ have no specific notation for being undiscovered (same in 2015). -DePiep (talk) 19:19, 10 January 2016 (UTC)

DS ideas
One thing that the interruption of the spectral sequence creates is that we don't have a large patch of the table (TMs plus Ln/An below and PTMs after) the same colour. If we are going to match a spectral sequence, then

I think the argument for a spectral sequence is pretty convincing, and matches electronegativity, first ionisation energy and electron affinity (as well as reactivity!) pretty well (with a few bumps and dips that we can probably smooth out). The slight problem is that the huge dip in reactivity at the noble gases (and the unique combination of high ionisation energy and high electron affinity that leads to it) is perhaps compelling enough to break the trend just for them.

So if I were to edit R8R's scheme to be more in accordance with the spectrum, I'd have a spectrum running from the alkali metals to the halogens, with the noble gases abruptly muted in colour, and then the trend can start again in the next row. The trend is about chemical properties, so it makes sense to mute the colours for elements with limited chemistry at standard conditions (the noble gases).

So I'd choose something like (forgive me for not making my own scheme, since I can't really choose colours well):
 * alkali metals: magenta
 * alkaline earth metals: violet
 * lanthanides: azure
 * actinides: blue
 * transition metals: green (preferably a bluish green to distinguish it clearly from the right)
 * post-transition metals: chartreuse (greenish yellow)
 * metalloids: (pure) yellow
 * polyatomic nonmetals: orange
 * diatomic nonmetals: red
 * noble gases: a light cyan, close to white, just as present (abruptly contrasting with the preceding red)
 * unknown chemical properties: the current grey

This puts the cool colours on the metallic side, and the warm colours on the nonmetallic side. Since yellow is clearly differentiated from green and red, it stands as a reasonable midpoint. The sequence can easily wrap around from diatomic nonmetals (with the halogens as a subset) to alkali metals, with the noble gases standing in between these infamously reactive elements as a bastion of calm. Double sharp (talk) 13:06, 9 January 2016 (UTC)
 * This does run into the "huge patch of the same colour" problem for those languages that do not distinguish blue and green as different colours (just different shades), though. But R8R's current scheme already falls into that, and since they are clearly distinct shades still, I think we can live with it.
 * What do you know, I finish composing this post and check R8R's sandbox, and he's edited it to be almost exactly the scheme I outlined above. Nice! (Though I think the polyatomic and diatomic nonmetal shades are too similar; I'll try tweaking the latter a little, to push it a little further towards the reddish end of the spectrum.) Double sharp (talk) 13:09, 9 January 2016 (UTC)
 * Oh, right, that makes it collide with the red colour for gases (although we could change that if we wanted to). What I think could be improved about his current version is that TM/PTM and poly-/diatomic nonmetals are a little too close, and that the contrast could be exaggerated a little by choosing shades of the same colours (green/chartreuse; orange/red) that are further apart on the spectrum. Double sharp (talk) 13:12, 9 January 2016 (UTC)

With regard to the next levels in the g- and f-blocks: since actinides are darker than lanthanides, superactinides should be darker still. I think, like R8R, that we should seriously consider eliminating period 10 from the extended table, since the idea of element 184 is treated with caveats by Fricke himself, and does not appear in recent studies (e.g. Pyykkö), and it appears that the second island of relative stability would probably appear earlier, at Z ~ 164 instead. We're not really sure what happens beyond Z ~ 172 with weird things happening with the nucleus. Double sharp (talk) 13:24, 9 January 2016 (UTC)
 * I definitely gonna chew on all of this (but maybe not coming week). Likely will create the set in my sandbox. Whatever happens, spectral sequnce has its dangers (distinction of neighbors), so it must be proven right.
 * As for the M'OIDS=yellow can I agree (irrespective of the neighbor colors even), also because we can only use one shade of yellow (it is too light for a second distinguishable yellow). That can be the full yellow then. More later. -DePiep (talk) 16:13, 9 January 2016 (UTC)
 * Or maybe, since the superactinides are going to be in their predicted shade (and hence on the lighter end), we should perhaps have lanthanides blue and actinides azure, so that the superactinides can be lighter still. Double sharp (talk) 14:18, 10 January 2016 (UTC)
 * Played around with this. So far, 1. I did engage the NG in the spectral sequence. Having them standing out looked a bit unneeded to me. (and after all, they are in that place #18 rightly by sequence). 2. assuming the super-An will be "predicted" all so have a lighter An/Ln color. Not a main PT color. 3. In the 360 deg color circle for 11 colors, I made steps op 30 deg (Hue numbers 0, 30, ...), using some extra space for the separation of: NG, s-, f-block (ie colors wider from each other there). 4. Did do the pair-swaps again: eg in purple pair, blue pair, green pair, red pair. Not Moids, not NG. 5. And trying white for unk-category (was grey). -DePiep (talk) 19:27, 10 January 2016 (UTC)
 * re ""huge patch of the same colour" problem" (think TM): I don't think this is a problem any more. Now that we use "different color/hue, same tone=pastel-thing" (R8R adopted too), color are not 'attacking' any more (as some 1st try colors were: flashing!). To me, the whole table now looks almost equally soft. I see no need to avoid a color for a big category, any more. -DePiep (talk) 19:34, 10 January 2016 (UTC)

Hey, I like that noble gas colour. It follows the spectral sequence, but it's not actually a spectral colour. Nice touch. ^_^

Current colour scheme:


 * alkali metals: blue (I don't see it as purple)
 * alkaline earth metals: violet
 * lanthanides: cyan
 * actinides: azure
 * transition metals: chartreuse (on the greenish side)
 * post-transition metals: green
 * metalloids: yellow
 * polyatomic nonmetals: red
 * diatomic nonmetals: orange
 * noble gases: magenta

Could we see the superactinide colour in a mockup? It won't be a basic colour, but should probably continue the trend from Ln to An to San. The white looks good. I don't think the colours are attacking each other anymore, although we should probably test this (especially for colour-blind viewers – I accept that 11 shades for them is going to be difficult, but at least neighbouring shades should look appreciably different). Double sharp (talk) 08:08, 11 January 2016 (UTC)
 * All sounds good. quick Re: Neighbor-distinction is a main requirement indeed (so I'm very happy with the pair-swap eg those next to the yellow Moid for this :-) ). Wrote about color calculations. Super-An color can be done, but is one of the side-issues (like contrast with SoM fontcolor etc). Choice of priority & time-spending: I think the main and defining and core problematic issue is the Legend 11; other topics should follow or require a fine tuning. A circular design process, while learning. A more elaborate sandbox to come (compare sets, automated predicted colors, ...). -DePiep (talk) 09:20, 11 January 2016 (UTC)
 * Is there a possibility to move the PTM hue out to 135°? It would make the gap between 90° (TM) and 180° (Ln) smaller and also make it more distinct from the chartreuse transition metals to the side. This is the one pair I think may be a hair too close. Double sharp (talk) 12:23, 11 January 2016 (UTC)
 * OK, I tried that. Double sharp (talk) 12:28, 11 January 2016 (UTC)
 * Ds, is there some numeric hue space somewhere to pull groups 12 and 13 more apart? However, this has low priority, the other distinctions are more important (and better be kept). -DePiep (talk) 08:21, 13 January 2016 (UTC)
 * If we do that then either the TMs crash into the metalloids or the PTMs crash into the lanthanides. (I think it ought to be groups 11 and 12 instead, but we'll save that for another time.) Double sharp (talk) 16:07, 16 January 2016 (UTC)

IUPAC project on the constitution of group 3
See here. Members look good. For more information contact the Task Group Chair: Eric Scerri . Sandbh (talk) 05:24, 28 March 2016 (UTC)
 * When I read "The question of precisely which elements should be placed in group 3 of the periodic table has been debated from time to time with apparently no resolution up to this point", I thought I might have slipped through the looking glass into WP:ELEMENTS. But then I saw "The task group will only concern itselve ..." (sic) and went looking for the edit button to correct the typo ... at which point I woke up and realized I wasn't on WP at all. Should be interesting to see the results ... but not nearly so interesting as being a fly on the wall during the committee deliberations. YBG (talk) 05:55, 28 March 2016 (UTC)
 * Note that their lede explicitly excludes any preferance between the 18- or 32-column PT. Now understand that all this also implies: an Sc/Y/*/** ambivalent PT is excluded. (because: an Sc/Y/*/** PT is not possible within the remit). All this as I said before. -DePiep (talk) 22:45, 28 March 2016 (UTC)
 * Presumably a Sc/Y/*/** table would still be OK as long there was a 3 over either La/Ac or Lu/Lr, to show which two elements completed group 3. Sandbh (talk) 09:32, 31 March 2016 (UTC)


 * .... in which case it is not a "Sc/Y/*/**" PT by definition & convention. -DePiep (talk) 16:14, 31 March 2016 (UTC)

"Mercury"
The usage and primary topic of "Mercury" is under discussion, see Talk:Mercury (planet) -- 70.51.45.100 (talk) 05:04, 8 April 2016 (UTC)

Radium melting point
The discussion if we should state that there are two values for the melting point given in the literature and that a very thorough radium review states a that there is a certain mismatch or that we go for the most quoted one is back on the radium page is back. I tried years ago to find sources for the melting point but I always come to one measurement of the curies back in 1910.

Two quotes showing that the 960°C value is also out there: The reported melting point of radium (960°C) is higher than that of barium (717°C). We observed a similar anomaly for actinium(1,050°C) and lanthanum (887°C). 

Metallic radium has a melting point of 700°C1 or 960”C3 and a boiling point of 1140”c. 

Old discussions: Please coment on the radium talk page. --Stone (talk) 20:06, 9 May 2016 (UTC)
 * Wikipedia_talk:WikiProject_Elements/Archive_12
 * WikiProject_Resource_Exchange/Resource_Request/Archive_7

WP:ENGVAR
It might be nice to go through the articles in our project and decide which articles have an already established national variety of English and make sure that all of them are properly tagged. As near as I can figure it, there are two sorts of tags, one that goes on the talk page to merely declare the correct WP:ENGVAR and another one that administrators need to add to a special subpage to generate an edit mesage. YBG (talk) 06:19, 12 May 2016 (UTC)

Image / Template:Infobox oxygen - has been deleted from Commons
The image for template:Infobox oxygen has been deleted from Commons. I cant find a new "liquid oxygen" image at commons, but I think we should have some kind of image in the infobox. Any ideas? Christian75 (talk) 05:38, 14 May 2016 (UTC)

Heavy metal (chemical element) is at FAC
Here. Sandbh (talk) 03:49, 6 June 2016 (UTC)

Elements 117 and 118: name endings
It was decided a long time ago that all new elements should have names ending with "-ium," even if element 117 is a halogen and 118 is a noble gas. There also was a proposal submitted to the IUPAC for discussion in 2015 suggesting the name for 117 should end with "-ine," and that of 118 should end with "-on." Now the proposals by the discoverers include the names "tennessine" and "oganesson". Could anyone help me verify that this proposal was actually approved at some point? The closest I could find so far is this: https://www.webelements.com/nexus/how-to-name-new-elements/ The site says the recommendations were "provisional," and now they're not available on the IUPAC's website (at least, I can't find them).--R8R (talk) 18:02, 8 June 2016 (UTC)


 * I found the formal paper and updated ununseptium with this info.--R8R (talk) 18:56, 8 June 2016 (UTC)
 * Aw, I was still rooting for Berzelius or Moseley to get an element. Alas it seems that nationalism begets more nationalism, and honouring great scientists of the past is not going to happen. (Thank you GSI for copernicium!) I suppose I will get used to the new names in time (and it seems that I was right in guessing 113 and 115 – I just didn't think they'd pull another Seaborg for 118), and even the -ine and -on endings. Double sharp (talk) 02:04, 9 June 2016 (UTC)
 * P.S. Please forgive my sulking. In retrospect, making friendly wagers IRL on element names was a bad idea. ^_^ Double sharp (talk) 12:50, 9 June 2016 (UTC)

Now comes the name-changing deluge from people who jump to conclusions from the news articles. Pardon me while I walk away from my computer and bang my head several times against the wall. Double sharp (talk) 15:16, 9 June 2016 (UTC)

Oh, and now the JWP reports are available: part one, part two. Double sharp (talk) 02:48, 10 June 2016 (UTC)

1993 TWG report
Unfortunately the original copy seems to have disappeared behind a paywall, but it's now here as well. Double sharp (talk) 08:59, 15 June 2016 (UTC)
 * P.S. See also this! Double sharp (talk) 09:05, 15 June 2016 (UTC)

a possibility
Since for once a significant number of us seem to actually be around, I wonder if we could (after R8R and I finish Pb) do something with N? It is currently absolutely terrible. Double sharp (talk) 15:31, 16 June 2016 (UTC)

Element category recolouring
We had a really nice mockup; is it going to happen? It is a lot easier on the eyes, with a big patch of green (okay, mostly chartreuse) instead of our current big patch of red and dull gray! Double sharp (talk) 15:28, 16 June 2016 (UTC)


 * I plan to dive into this again in a few weeks. Except for nicer colors at first sight indeed, I also want it to be professionally good (webdesign quality). It was labeled `2016` for a reason ;-) -DePiep (talk) 09:11, 17 June 2016 (UTC)

Regarding the extent of use of the IUPAC systematic names
And apparently, the main reason for this article's existence was the way we talked about the systematic names! (^_^) (This is from IUPAC.) Double sharp (talk) 11:57, 21 June 2016 (UTC)


 * may I ask you to set up a separate page where you would copy any links you post here? Some of them (including this one, which even made me want to ask you for this) are great to spice up writing in articles with facts, but in three months 62 days, they're going to be lost in the archives. If you also set up a layered structure of these links (similarly to folders in a computer), they may still be very useful later on.--R8R (talk) 13:36, 21 June 2016 (UTC)
 * OK, I'll create WikiProject Elements/Links. Double sharp (talk) 13:44, 21 June 2016 (UTC)
 * ✅, at least the ones I remember posting here or are still online. (Alas that means no Fricke. >_< But we've pretty much mined all his stuff already.) Double sharp (talk) 13:52, 21 June 2016 (UTC)

New names
I've started a discussion over at. Editors in this project may wish to contribute to the discussion. And we may wish to have a more global discussion here. YBG (talk) 15:35, 9 June 2016 (UTC)
 * See also Talk:Tennessine: Nergaal (who should know better) by CRYSTALBALL OR moved Uus into Tenessine. -DePiep (talk) 00:31, 11 June 2016 (UTC)
 * Closed as: move article (back) to be Uus. -DePiep (talk) 10:09, 12 June 2016 (UTC)


 * Just an interesting note: the RIKEN team also motivated their proposal for nihonium with this: The team  also  hopes  that  pride  and  faith  in  science will displace the lost trust of those who suffered from the 2011 Fukushima nuclear disaster. Curious, but they could not go without mentioning Fukushima somehow I guess. -DePiep (talk) 10:09, 12 June 2016 (UTC)
 * From what I have read (though I'm not entirely clear on the details), there really was a lot of lost trust that is still going on now, so I can totally understand why they included this statement. Hopefully the upcoming appearance of nihonium on all the periodic tables will replace at least some of it with pride. Double sharp (talk) 14:22, 13 June 2016 (UTC)
 * 113: Ununtrium &rarr; Nihonium, Nh
 * 115: Ununpentium &rarr; Moscovium, Mc
 * 117: Ununseptium &rarr; Tennessine, Ts
 * 118: Ununoctium &rarr; Oganesson, Og
 * DePiep (talk) 23:42, 12 June 2016 (UTC)


 * : I question this revert in List of elements. The addition is in a separate section (so not overwriting the current systematic names), just to add the etymology of the new names. Your es says "the new names are provisional and are only mentioned when they are the focus" (I'd say: proposed not provisional, but alas) - which is right what this section is about. Of course there we should describe the etymology of the proposals, it's serious enough by RS to have in in the encyclopedia. (we even explain eka- names and aluminum somewhere, so why not these?). I propose inclusion of such a separate section. -DePiep (talk) 15:07, 13 June 2016 (UTC)
 * Ah, now I see what you were thinking: it confused me because the rows were duplicated with the systematic names again (instead of nihonium and the others). I'll re-add it. Double sharp (talk) 03:04, 14 June 2016 (UTC)
 * I have 3 points deducted for my sloppyness. -DePiep (talk) 07:34, 14 June 2016 (UTC)

Etymologies
A few questions I'm rather inclined to implement (1b) or (1c) and then opting for (2c). I'm also leaning toward (3b) and (4b). My main motivator is to reach a consensus now before having to react some IP editor. Comments? YBG (talk) 04:40, 14 June 2016 (UTC)
 * 1) How should the four proposed element names be included in List of chemical element name etymologies?
 * (1a) not included at all  (current state)
 * (1b) included in an adjunct table  YBG (talk) 04:31, 17 June 2016 (UTC)  YBG (talk) 09:00, 25 June 2016 (UTC)
 * (1c) included in the main table{
 * 1) How should the four proposed element names be included in List of elements?
 * (see also the discussion between Double sharp and DePiep above)
 * (2a) not included at all
 * (2b) included in an adjunct table (current state) previously
 * (2c) included only as footnotes to the systematic names, with a link to the etymology article?
 * (2d) included in the main table but using 2 so as to subdivide the Name and Symbol columns only
 * (but of course, two completely separate rows would be generated as soon as the sorting option is used)
 * 1) How about the articles listing of places and scientists whose names are used in chemical element names?
 * (3a) wait to add them after the names become official
 * (3b) add them now but in a separate "proposed name" grouping YBG (talk) 05:51, 17 June 2016 (UTC)
 * 1) How about the templates Chemical elements named after places and Chemical elements named after scientists?
 * (4a) wait to add them after the names become official
 * (4b) add them now but in a separate "proposed name" grouping YBG (talk) 06:54, 17 June 2016 (UTC)
 * It's not just the IP editors, but I understand your point very well. I'd advocate consistency: since we currently are at (2b), I could accept that and consistently use (1b), (3b), and (4b). (2d) is a beautiful idea that I am rather taken with, but I am concerned (possibly needlessly) that it may ruin the sorting. Double sharp (talk) 12:00, 14 June 2016 (UTC)
 * I'm inclined to support all the (b) options as well. When the names are finalized, we can integrate everything. shoy (reactions) 13:26, 14 June 2016 (UTC)
 * Regarding option (2d), I have added and then reverted it again. You can see how it looks here. Sorting works OK except that any sorting creates two complete rows, even if the table is sorted back into its original order. The only way to restore the subdivided cells is by reloading the page. Take it for a test drive and let me know. If it meets with a consensus approval, we can restore it and remove.
 * Side note: In the 62 seconds it took me to revert my change, a total of 158 other edits were made to WP. YBG (talk) 05:06, 17 June 2016 (UTC)
 * Perhaps it would be better to mention in the etymology section that these are proposed names, instead of leaving it to a footnote that people may not read (and which may be confusing). But the sorting bug ruins it for me, which is a pity. Double sharp (talk) 05:40, 17 June 2016 (UTC)
 * The same thing happens to Ytterby when sorting the main table in . YBG (talk) 06:00, 17 June 2016 (UTC)
 * I find that more acceptable, since we are listing elements there, not the namesake that gets duplicated. Double sharp (talk) 06:08, 17 June 2016 (UTC)
 * I've tried (and reverted) another idea here. No sorting issue now unless you are insisting that it sort by the still-proposed names or corresponding symbols/etymologies. Thoughts? YBG (talk) 06:54, 17 June 2016 (UTC)
 * Much better! (BTW, tennessine would be Ts; it can't be Tn, since that's thoron, 220Rn.) Double sharp (talk) 08:28, 17 June 2016 (UTC)
 * I've implemented (1b) and (3b). I plan to do (4b) soon. YBG (talk) 05:51, 17 June 2016 (UTC)
 * And now (4b) is also done. YBG (talk) 06:54, 17 June 2016 (UTC)
 * Not sure what happened to make me think I'd done (1b), 'cause I didn't even try. Sigh. YBG (talk) 07:09, 17 June 2016 (UTC)


 * In general, I do support mentioning them, and oppose mentioning them in any main table/list/feature right next/below to the systematic name. Maybe make a standard footnote (in a template) to explain the situation? BTW, sorting problems may not force our content choices. And there is Sort to control the sortvalue=/=shown value in a table cell. -DePiep (talk) 09:17, 17 June 2016 (UTC)
 * Ideally, yes, sorting problems should not force our content choices. But when I'm sitting on the fence, they do make it easier for me to make my decision! (^_^) The current status quo with all the (b) choices is already an adequate solution, though, and seems to have the greatest amount of support here. It is in any case much better than the way we did it in 2012, which was to just ignore the proposed names completely outside the Fl and Lv articles. Double sharp (talk) 15:14, 17 June 2016 (UTC)

a proposal regarding old GAs
So, R8R Gtrs has once again brought to my attention that some of our older GAs (e.g. C, Sc, Hf, Tl, chalcogen) do not really live up to current standards, but since they have the plus sign, nobody is going to think anything is wrong, and they will for the most part not improve.

My suggestion: WP:CHEMS refuses to recognise GA and FA in its banners. Why don't we do the same? We can note that an article is a GA, yes, but in terms of referencing and/or chemistry it needs help. So we can have on the PTQ a yellow cell (C-class) with a plus sign, showing that it's not all right, and preventing us from looking at the green PTQ and thinking everything is fine. Double sharp (talk) 14:26, 22 June 2016 (UTC)


 * I entirely support the proposal.--R8R (talk) 15:06, 22 June 2016 (UTC)
 * When I get more time to do major edits (i.e. not now, but soon) I will do a preliminary assessment of our articles according to this standard and put it here. I would probably be very strict and unwilling to forgive the mortal sin of not writing a good chemistry or compounds section, and thus robbing us of the opportunity to get to know the element's personality. ^_^ Double sharp (talk) 13:52, 26 June 2016 (UTC)

Elements 119 and 120
After the recent triumphs regarding elements 113, 115, 117, and 118, I imagine that efforts to synthesise the first period 8 elements will be redoubled. Since there do not yet seem to be guidelines about this, I propose the following:

Furthermore, when compounds of an element are first synthesized, the oxidation state formatting must change, as not all will be predicted anymore. The oxidation state that has been found should be left alone; the others will be parenthesised. Meitnerium gives the format before compounds are synthesized and hassium gives the format after. Double sharp (talk) 16:17, 11 June 2016 (UTC)
 * 1) When a new element is first synthesized, the predicted standard atomic weight is removed and replaced by the mass number (in square brackets) of the most stable isotope synthesized.
 * 2) The discovery field in the infobox must of course be filled.
 * 3) We should no longer used "predicted" shading for the infobox, instead using the "unknown chemical properties" shade.
 * 4) Nothing else in the infobox changes.
 * 5) No gaps should be left; if element 120 is discovered before element 119, so be it. Both will be placed on the table with links, but 119 will be marked as "undiscovered" (presumably the way we marked 117 so long ago, with a borderless cell).
 * 6) When elements 119 and 120 are synthesized, we should simply add them under Fr and Ra in the present table. There is no need to add the g-block extensions until element 121 is synthesized.

Regarding the creation of articles for elements 121 and above: a "normal" transactinide article has the sections "history" (including synthesis attempts) and "predicted properties" (chemical, physical, and atomic). If you can summarise all of this in two paragraphs (one for history and one for predicted properties), don't create the article yet. If it balloons to the current size of the ununennium article, go right ahead and create the article. Another guideline would be to ask: how full is your infobox? If you can only fill in a few items, forget it. If you can fill many items and even have some that don't have fields in the infobox, you can probably go right ahead and create the article. Double sharp (talk) 16:21, 11 June 2016 (UTC)


 * Looks good to me. Thank you for thinking ahead. As far as process goes, I think we should
 * Reach a consensus on these guidelines
 * Formally close the discussion
 * Keep a link to the closed discussion so we can remind ourselves and others of what has been decided.
 * YBG (talk) 18:41, 11 June 2016 (UTC)


 * I agree in general, but I'm calling for determining the specifics as the problems to be solved appear. We're a small project, I don't see the point for three or five people to determine the rules to set in stone, and things change, and so on. Again, I agree with the general principles (no g block until we have a g block element, etc.; except I'm not sure we'll be better off without a gap for 119, even the IUPAC is fine with gaps, but I won't really argue, either). If other things leave room for speculation, then I'm fine (don't think there necessarily should be a hard criterion to have or not have an article).--R8R (talk) 19:47, 11 June 2016 (UTC)
 * Yeah, I don't think of it as a hard criterion so much as a guideline if you're not sure. Essentially, it just asks you to consider whether the material you have is enough to write a full-length article on the element. Only the general principles #1-#6 I think need to be put down first. Regarding 119, I thought it would be better to avoid the gap because that's what we used to do with 117, but I can see arguments both ways. Double sharp (talk) 04:55, 12 June 2016 (UTC)


 * My reply per number (original text compacted):

1. When element first synthesized, standard atomic weight = [mass number] of most stable isotope
 * Sure, as before. (but bracket notation "[351]" could be confusing with regular CIAAW notation wrt uncertainty. Minor here).
 * True. But CIAAW uses the brackets too, so it's their problem. ^_^ Double sharp (talk) 13:13, 27 June 2016 (UTC)

2. discovery field in the infobox filled
 * Sure, adding like "(unconfirmed)" right?
 * Probably not, given that we didn't have "(unconfirmed)" for 113, 115, 117, and 118. IUPAC is very slow at this! Element 115 was already confirmed in 2013! Double sharp (talk) 13:13, 27 June 2016 (UTC)

3. not "predicted" shading for the infobox, but "unknown chemical properties" shade
 * See below. We have "predicted element" and "unk property", chemical or physical (for any property apart). Properties can be: metallic category, phase at r.t., etc. I fully support that we diverse between "unk element" and "unk property X". (Note that historically, we at WP:ELEM used "unk" indiscriminately. This proposal clearly separates "unk element" from "unk property Y". Good).

4. Nothing else in the infobox changes
 * Well, anything can by RS. What if the discoverers, with first synthesysis, publish an, eh, "phase at r.t."?
 * True, but highly unlikely. If this happens, of course, it can and should be added. Double sharp (talk) 13:13, 27 June 2016 (UTC)

5. No gaps should be left
 * Don't understand. Gaps in the PT? Missing article E121 when E122 is synthesized? Anyway I don't think any 'no gaps' rule should be a MOS in this. Better: see what science RSs have and comes up with.
 * I don't feel that strongly one way or another about it, but I think you've understood what I meant. Indeed it would be useful to see what RSs come up with, if E120 should for example be synthesised before E119. Double sharp (talk) 13:13, 27 June 2016 (UTC)

6. ''When elements 119 and 120 are synthesized, we should simply add them under Fr and Ra. no need to add the g-block extensions until element 121 is synthesized.''
 * ... as they are today. And RS g-block predictions can alwaysd be added in context (extended PT topics, for example).
 * Of course. The difference would be that we would start showing E119 and E120 on our non-extended PTs as well. Double sharp (talk) 13:13, 27 June 2016 (UTC)


 * Pulling this in general:
 * Our coloring by legend should follow the actual fact. So if property X is 'someting', we use the corresponding coloring. This discussion is actually more about: "what to do with unconfirmed/unk/disputed" properties.
 * Elements can only have three statuses: unk, synthesized, proven (e.g. E118 has made these steps recent years; group "synthesized" is empty since December)
 * Any single property can only have three statuses: unk, Bold textpredicted, proven/agreed.
 * And yes we use colors accordingly.
 * We can add RS statements like "(predicted)" to any property. Especially in context, 'speculations' (actually: scientifically based claims) are allowed. For example: Extended periodic table can have a g-block showing).
 * For the rest, I prefer R8R's remark that we can wait until the situation occurs instead of pre-emptively setting things in stone.


 * Todo: check & maintain that the three statuses (three per element, three per property) are written & colored consistently.
 * -DePiep (talk) 17:41, 19 June 2016 (UTC)

DS's initiative to get easy GAs in the main body of the table
(Yes, yes, I know the header presupposes an 18-column table. In my defense I find that the lanthanides and actinides, except blockbuster Th, U and Pu, get hilariously few views and so are not worth the trouble.)

For this purpose I have gotten In and La to GAN. (La because my mental periodic table will always be Sc/Y/La/Ac through force of habit, and because it is so in most textbooks, and because La would have higher views than already-GA-but-honestly-B-sorry-R8R-I-couldn't-help-it Lu.) After returning to active work Ga will be next. No promises about Sr because I find it very difficult to get worked up about and it is further away.

After that are the scary ones (period 3, Ca, As, Sn, halogens). Sn could mostly follow Pb in structure, actually. Similarly Na can easily follow the K structure and the heavier halogens can follow the F structure. (Tempted to do iodine because it is pretty and I like purple. That's not a good reason at all, of course, but it is a popular element.)

(PS to R8R Gtrs: one other reason to do this is because you mentioned that perhaps people don't stay here and pick elements because the project looks from the announcements and achievements as though it's been half-dead since 2014. Now I am creating the impression of activity, since FA work takes a long time and doesn't look so impressive to people who are just passing by!) Double sharp (talk) 13:09, 27 June 2016 (UTC)


 * Unfortunately, I find myself not understanding what exactly is being suggested, could you clarify?--R8R (talk) 14:42, 27 June 2016 (UTC)
 * With more clarity (I admit I can't quite understand it myself today):
 * You mentioned on my talk page IIRC that one reason why editors may not want to join us was because we used to look half dead, and for that reason I got In, La, and 120 ready to make it look like more work was going on. (I really cannot afford to spend much time on WP for the next few months, so you've probably seen almost the last of me for a while: I will work on the currently open GANs as the reviewers request so that they pass, and I will help you for Pb, but I really will not be able to be seen anywhere else. I'm sorry! Th FAC will wait till I return with full force in December.)
 * BTW, regarding the group articles: it strikes me that only groups 2 and 17 are really important to get done. The others are either a completely motley collection (13–16) or they are transition metal groups and hence you need to look at across-period similarities as well. So when I return in full force that will happen. Double sharp (talk) 13:27, 28 June 2016 (UTC)

If anyone wants to work on the heavy pnictogens...
Biological Chemistry of Arsenic, Antimony and Bismuth (I'll post this on the links page too). Double sharp (talk) 11:10, 3 July 2016 (UTC)

Etymology templates
Does anyone else think it would be a good idea to combine and  into ? YBG (talk) 07:29, 25 June 2016 (UTC)
 * I've got a draft of what I have in mind at . Comments more than welcome. YBG (talk) 08:28, 25 June 2016 (UTC)
 * Such a title would seem to imply that every element was included, and it is not really clear how to categorise some of them in a neatly packaged navbox. Some are descriptive (Ne, Cr, La, Dy); some are mythological (Ti, V, Nb, Ce, Pm, Ta, Th); some are really ancient names (S, Fe, Cu, As, Ag, Sn, Sb, Au, Pb); and some refer to other elements (Pa)! Double sharp (talk) 09:06, 25 June 2016 (UTC)
 * The reply by Double sharp triggered this thought with me: shouldn't those two navboxes be deleted completely? They are not defining or topical overviews. We also don't have "Element names starting with an A", nor "Elements named after something". The etymology list for all elements should do. -DePiep (talk) 13:01, 26 June 2016 (UTC)
 * I tend to agree. I doubt that many people actually use such classification for anything, and there's no actual reason to have a whole template for elements named after people, etc.--R8R (talk) 13:04, 26 June 2016 (UTC)
 * Agree. Double sharp (talk) 13:50, 26 June 2016 (UTC)
 * While not disagreeing with any of the above, let me point out another use of navigation templates that I find myself using: they provide a nice concise overview of a topic area. In this case, it is rather more concise than the etymology list. YBG (talk) 03:11, 27 June 2016 (UTC)
 * It is indeed "rather more concise", mostly because the majority of the elements are not on it. So while each of these templates could make some sense alone (although I am pretty sure that nobody actually uses these categories and mentions them alone), they don't make sense combined into one IMHO. Double sharp (talk) 08:32, 27 June 2016 (UTC)


 * So I've put up those templates for deletion, see what happens. Next: I find the etymology column in List of chemical elements a bit cramped and out of place. Also existing are articles List of scientists whose names are used in chemical element names ans List of places used in the names of chemical elements. DePiep (talk) 21:05, 27 June 2016 (UTC) -- signature duplicated by YBG (talk) 04:32, 28 June 2016 (UTC)

Revised etymology article

 * Why don't we create article Etymology of names of chemical elements ? With enough space for all the info, nice to read. (or: merge the two lists & expand into full list). -DePiep (talk) 21:05, 27 June 2016 (UTC)
 * I agree that the etymology column in list of chemical elements is cramped and out of place. I'd like to see it deleted, merging it with list of chemical element name etymologies. But the table in that article has its own set of problems, which I've been cogitating over and haven't quite figured out how to resolve. One thing I have decided is that elements like Hg, Au and the like ought to have two rows - one for the name etymology and one for the symbol etymology. The current table tries to do this in two columns and the result is really ugly. The table is, after all, a list of etymologies and not elements. Au and gold have two different etymologies and so should have two rows whereas C and carbon have but one etymology and so should have only one row. YBG (talk) 21:59, 27 June 2016 (UTC)
 * Aha, so already List of chemical element name etymologies exists. Well, that is where we will merge all etymology into then. The rest is formatting (ouch, sentences in small table columns are really ugly). Andd yes, those symbols must get their place (row) too. -DePiep (talk) 22:33, 27 June 2016 (UTC)


 * See Draft:Etymology of names of chemical elements. IMO, it should be a full article not a list (clarifying texts). And when table format is too limited, we can resort to one-element-one-subsection. Most important: one single target article for all etymology. -DePiep (talk) 23:25, 27 June 2016 (UTC)

Recap, restart
I like the idea of making it a full-fledged article and not just a list. But I think we should still have sortable table. Here's some general ideas: You are welcome to disagree with any of these despite my having expressed it as though there were no alternatives. This is just a starting point. YBG (talk) 07:47, 28 June 2016 (UTC)
 * 1	Above all, Keep it simple
 * 2	One etymology per item in the main table
 * 2.1	Single item if name and symbol have the same origin
 * 2.2	Two items for Sb, Au, Fe, Pb, Hg, K, Ag, Na, Sn, W, Cu YBG 2016-06-30
 * 3	Info for each item in the main table
 * 3.1	Z
 * 3.2	Element name & symbol
 * 3.2.1	Name (Symbol)
 * 3.2.2	Symbol (Name) -- additional row for Sb, Au, Fe, Pb, Hg, K, Ag, Na, Sn, W, Cu YBG 2016-06-30
 * 3.2.3	No extra row if 1st letter matches but 2nd doesn't (Cf = Californium) (except Cu) YBG 2016-06-30
 * 3.3	Category -- toponymn, eponym, descriptive, descriptive (color), ...
 * 3.4	Language of origin -- Do we really need to list multiple languages?
 * 3.5	Original meaning -- Can this be simplified?
 * 4	Avoid word wrap in table cells at all costs
 * 5	Things to keep separate from the main table
 * 5.1	Unadopted proposed names
 * 5.2	Mendeleev’s systematic names
 * 5.3	IUPAC systematic names
 * 6	Other narrative sections
 * 6.1	History of naming
 * 6.1.1	One ¶/§ per era of timeline of chemical element discoveries
 * 6.1.2	Controversies
 * 6.2	Origins of names
 * 6.2.1	One ¶/§ per category – toponym, etc.
 * 6.2.2	Systematic naming – Mendeleev, IUPAC
 * 6.2.3	IUPAC rules
 * Quick re: 2.2: in these cases (Hg), split rows after Z-column or so.
 * 3.3: category is good addition
 * 3.4 lang of origin, meaning: keep in one cell, eg for Ac write "ἀκτίς (aktis) (Greek), meaning 'beam'" in one cell. Sentence is more easy reasing, and saves width.
 * 3.5 original meaning: simplified maybe, but not cut off into shouts. This is the main point of the table!
 * 5 and 6: sure not in main table, but deserve a section. -DePiep (talk) 13:55, 28 June 2016 (UTC)
 * Started a table setup at Draft:Etymology of names of chemical elements. Note that split rows still sort nicely. -DePiep (talk) 14:07, 28 June 2016 (UTC)
 * Here are some more thoughts:
 * The Z column should be the only 2 and so it belongs on the left.
 * The 2nd row for Hg should include all columns to facilitate sorting, including alpha sorting by names+symbols: Actinium (Ac) // Mercury (Hg) // Hg (Mercury)
 * The general category seems like it should come before the more specific etymology
 * I have implemented these here in the sample table. YBG (talk) 03:59, 30 June 2016 (UTC)
 * Here are some questions:
 * Q1: Can we avoid paragraph-long descriptions? We've got 128 rows (118 + 11 per 2.2)
 * Q2: Can we just use transliterations? I like (& read) scripts, but they don't help readers.
 * Q3: Can we have just one language per entry? I suggest the immediate source.
 * Q4: What about a year named column, and making it the original sort?
 * YBG (talk) 04:29, 30 June 2016 (UTC)
 * I've added Cu to the list of elements needing two rows as Cu is from Latin Cuprum, not English Copper. In all other cases where the symbol's 2nd letter doesn't match name's 2nd, it matches a subsequent letter, so I presume the symbol & name have the same origin. But there may be one or two other exceptions. YBG (talk) 07:19, 30 June 2016 (UTC)
 * Nice table improvements.
 * A1: must be readible sentences, it what it is about (but current Hg text too long indeed). See after we've build composed the new table?
 * A2: You mean remove the greek 'ἀκτίς' thing. There must be a guideline for writing diff languages and scripts. Can we link to elwiki (greek) -- if it has that word?
 * A3: Sure we need to take a 2nd look at the texts (Latin in the HG row?); it started with existing text.
 * A4: Link Add 'year' column sounds good, but should not have extra text (to save width; any text needed should be in the description).
 * Q5: imo, the table should be ordered by element name basically. Not Z. And keep Hg below/with mercury.
 * Let's add a few more. -DePiep (talk) 12:16, 30 June 2016 (UTC)
 * Found this: MOS:FORLANG. -DePiep (talk) 12:24, 30 June 2016 (UTC)
 * Q6. So there are up to four units involved for the origin: original word (in roman script), original script spelling (eg greek), language, meaning. Plus some extras. Shall we shift the first three into one column?
 * Changed table to have readers search word in leftmost column. Adding hidden "_" to sort symbols together, once sorted. -DePiep (talk) 12:58, 30 June 2016 (UTC)
 * I think we are getting closer and closer
 * A1a: The current sample doesn't have any complete sentences, so I presume you mean sensible phrases/clauses
 * A2a: Yes, I'd like to remove the Greek stuff
 * A3a: What I mean by 'immediate source' is that we avoid long etymological chains, e.g., if the name is from Latin, and the Latin derived from Greek and the Greek from Arabic and the Arabic from Persian, and the Persian from proto Indo European, then we would only list the immediate source language, Latin, and not the ultimate source or any of the intermediate sources.
 * Q3.1: What do we list for elements which are native English words (e.g., gold)?
 * Q3.2: What about elements named for minerals? Boron was named by an English speaker for Borax, a native English word, so we would list English as source language since we're interested in the etymology of Boron, not that of Borax.
 * Q3.3: What if it was named by an XX speaker, and the mineral has a different name in English? What if the mineral has the same name in English? What if that English name wasn't in common use in English at the time? These are the problem children which probably need to be decided on a case-by-case basis; at this point, I'd just like to see if we can agree to generally list only one language and only go to multiple languages if there is a consensus that it really is necessary.
 * A4a: Agreed, just 4 digits and nothing more. If it seems like it needs more, the extra info should go in the explanation or in a footnote.
 * A5: I agree that the original sort should keep the Hg and Mercury rows together. There are two ways to do this: sort by Z or sort by the year of naming. I lean toward the latter, as it seems more appropriate in the context of etymology. This would tend to cluster Levoisier's x-gen's together and the elements named after the planets and asteroids.
 * A6: I agree it would be nice to merge several columns together. But if we do so, the language should come first as it is the only meaningful thing to sort by. Proposed order (1) language (2) original word (3) transliterated word (4) meaning (5) reason for naming. For example:
 * Praseodymium: Greek πράσιος δίδυμος (prasios didymos) "green twin" because its green oxide helps distinguish it from the neodymium it occurs with in the mineral didymium.
 * Neodymium: Greek νέος δίδυμος (neos didymos) "new twin" because it is hard to distinguish from the praseodymium it occurs with in the mineral didymium.
 * (This could all be a single column or it could be broken up into 2, 3 or more)
 * Q7: How should the extra symbol rows sort? Should they be sorted together using a hidden "_" or would it be better to short them alphabetically so that you'd see all of the letters together? I think the latter would be better so that the reader could use the sorting to see all of the potential symbol clashes together. If they don't sort together, then would some graphical technique (color, etc.) be helpful to distinguish these rows from the others?
 * YBG (talk) 22:10, 30 June 2016 (UTC)
 * I'm sorry, t oo muche details & levels together. I prefer to play around. (... for the moment) -DePiep (talk) 00:24, 1 July 2016 (UTC)
 * About the explanation/description: re "multiple languages if there is a consensus that it really is necessary": this sums up a main issue here. I do think we should allow for, or even aim for readable sentences, possibly paragraphs (taking all that space). So there could be a chain of words (you example is extreme), but say PIE and old Eglish for gold are welcome.
 * About foreign scripts: OK, leave out (even more so when we have a good link or, wl). Roman script will do. So like: "From Greek: aktis: 'beam'" (+wl)
 * About columns & grouping: I'd say meaning & explanation (both in 'sentences') in one text column. (I noticed I had a different need for Au and Ac. Not sure).
 * About sorting: is a bit minor. For now, I'd say when sorted by that column, symbols together.
 * -DePiep (talk) 17:13, 3 July 2016 (UTC)

Article renaming discussion
You are invited to participate in a discussion at. Only four editors have been involved so far, and while they agree the article should be renamed, they disagree about the best new name. YBG (talk) 04:26, 4 July 2016 (UTC)

German Wikipedia FAs and GAs
In German Wikipedia, americium, argon, arsenic, berkelium, caesium, californium, curium, europium, gallium, helium, hydrogen, indium, krypton, lead, lithium, lutetium, manganese, osmium, ruthenium, technetium, tellurium, vanadium, xenon, ytterbium, and zirconium are featured articles. Now I realise that their requirements on sourcing are less strict, so most of these would only lead to GA here. Nevertheless, of these, arsenic, gallium, and indium are not at least good articles here already (although gallium and indium have been nominated, so it's really just arsenic), and so a translation would help.

Their good articles are chlorine, einsteinium, fermium, fluorine, gold, hafnium, neon, plutonium, sodium, rhenium, rhodium, sulfur, and strontium. These could only plausibly help on the worst articles that are only C-class (chlorine, gold, sodium, sulfur, and strontium), and are still somewhat weak on citations from what I saw of their chlorine article. Double sharp (talk) 07:10, 12 July 2016 (UTC)

ENGVAR articles
I created. Hidden, maintenance, etc. Any content page should be in there (article, category). The category must be added manually. There is no automated template. -DePiep (talk) 00:29, 7 July 2016 (UTC)
 * Thank you for responding to my original post which has been recently archived to . YBG (talk) 00:03, 15 July 2016 (UTC)

Natural curium?
CRC 94th edition says "Minute amounts of curium probably exist in natural deposits of uranium, as a result of a sequence of neutron captures and &beta; decays sustained by the very low flux of neutrons naturally present in uranium ores. The presence of natural curium, however, has never been detected." It does not say this for Am, Bk, or Cf, despite Emsley. Indeed, 247Cm is certainly an extinct radionuclide (and while it was still live, it would have meant that there were 96 naturally occurring elements on Earth, as it decays to 243Pu, 243Am, 239Np, 239Pu, and then rejoins the actinium series at 235U), and 244Cm should be found as the double-beta decay product of primordial 244Pu. But given that it has not been detected (though natural 247Cm has been looked for), I would not change Cm to "from decay".

With regard to the first few nuclides on the list of nuclides that are just too short-lived to be primordial: 92Nb along with 94Nb has been found in nature from muon capture (presumably of natural molybdenum). Similarly, 205Pb is produced by muon capture of natural 209Bi. 236U is of course known from neutron capture by 235U and as a daughter of 244Pu, while 129I is a cosmogenic nuclide from spallation of Xe. 247Cm alas would be extinct because there isn't really a way to produce it anymore (except by really slow s-process capture with 238U as the starting material as Emsley claims, but there are no corroborating sources for his claim). 182Hf is also an extinct radionuclide, but it would rise once more far into the future when 186W has appreciably alpha decayed. 107Pd is an extinct radionuclide: I suppose you could say it exists on Earth thanks to meteorites.

But even 247Cm produced at Oklo would have been slashed in half at least sixty-four times, so I am not hopeful. Double sharp (talk) 12:41, 17 July 2016 (UTC)

extermination of the B-class
In the spirit of creating the impression that more work is being done than actually is, and to do some star-collecting, why not get rid of the five B-class articles (that aren't already at GAN) and get them up to GA? Of them only iron and silver really badly need to improve past that.

Comments:
 * Iron: not bad but needs more history if it is taken further. For GA it just needs some finishing touches re referencing.
 * Gallium: applications need a look-through, to see which ones are the really major uses (cf. what I did to indium, which I could only do thanks to the talk-page comments). Characteristics are fine and only need extra referencing.
 * Arsenic: a strange article that achieves its B status by virtue of alternating between GA-level and C-level sections. There is a review on the talk page, so I will recommend that it be looked at instead.
 * Silver: reasonably detailed, but terrible referencing
 * Radium: see the GA review; it needs a bigger history section

The other B-class articles (indium, lanthanum, bohrium, element 120) are already at GAN, after I worked on them to that level (though for indium it was more a case of minor work on the excellent base that was already present). Double sharp (talk) 08:50, 10 July 2016 (UTC)
 * I decided to GAN Fe right away. It is not that far (B/GA difference is mostly citations) and it will be like Pb GAN all those years ago. Double sharp (talk) 15:42, 10 July 2016 (UTC)

Hard to decide which one to do next. Since I was there when arsenic and radium failed and do not have any new sources they will fail again unless I go looking. Hmm...silver or gallium? The former demands more responsibility and taking it to FA later, and the latter will be a retread of indium. Double sharp (talk) 15:27, 11 July 2016 (UTC)
 * ...probably gallium Double sharp (talk) 16:02, 11 July 2016 (UTC)

I did gallium.

I have an idea to do sodium, following the potassium model, and get the alkali metal GT. Double sharp (talk) 15:14, 18 July 2016 (UTC)

Request for assistance
In Refractory metals, we have: Definition::Most definitions of the term 'refractory metals' list the extraordinarily high melting point as a key requirement for inclusion. By one definition, a melting point above 4,000 °F (2,200 °C) is necessary to qualify.[2] The five elements niobium, molybdenum, tantalum, tungsten and rhenium are included in all definitions,[3] while the wider definition, including all elements with a melting point above 2,123 K (1,850 °C), includes a varying number of nine additional elements, titanium, vanadium, chromium, zirconium, hafnium, ruthenium, rhodium, osmium and iridium. Transuranium elements (those above uranium, which are all unstable and not found naturally on earth; rutherfordium is predicted to have melting point 2400 K or 2100 °C) and technetium (melting point 2430 K or 2157 °C), being radioactive, are never considered to be part of the refractory metals.[4]"

I would like to change this to: Definition::Most definitions of the term 'refractory metals' list the extraordinarily high melting point as a key requirement for inclusion. By one definition, a melting point above 4,000 °F (2,200 °C) is necessary to qualify.[2] The five elements niobium, molybdenum, tantalum, tungsten and rhenium are included in all definitions,[3] while the wider definition, including all elements with a melting point above 2,123 K (1,850 °C), includes a varying number of nine additional elements: titanium, vanadium, chromium, zirconium, hafnium, ruthenium, rhodium, osmium and iridium. Transuranium elements (those above uranium, which are all unstable and not found naturally on earth), being radioactive, are never considered to be part of the refractory metals[4], although rutherfordium is predicted to have melting point 2400 K or 2100 °C) and technetium a melting point of 2430 K or 2157 °C.

New version okay?

Thanks -- Jo3sampl (talk) 01:08, 15 July 2016 (UTC)
 * Go ahead, you don't need to ask before you edit an article of interest to us. Sandbh (talk) 12:58, 17 July 2016 (UTC)
 * Well, there is a little problem, since your proposed version makes it sound like technetium is a transuranium element, which it isn't. I'd change your last sentence to "The artificial elements, being radioactive, are never considered to be part of the refractory metals, although technetium has a melting point of 2430 K or 2157 °C and rutherfordium is predicted to have melting point 2400 K or 2100 °C). (I know perfectly well that technetium is not completely synthetic, but it might as well be.) Double sharp (talk) 14:05, 17 July 2016 (UTC)
 * Thanks much -- done -- Jo3sampl (talk) 15:25, 21 July 2016 (UTC)

Why I still think getting articles to GA is important
Because, we are really not as close as it looks like we are. The elements from fermium onwards have easily-written cookie-cutter articles that are easy to collect stars for, but do not actually matter to the average reader. (Astatine and francium are also somewhat in this category of "nobody cares", but they're somewhat grandfathered in because of their appearance on the hallowed list of 94 natural elements.) We have been concentrating almost exclusively on such elements for the last few years, and very little has changed with the elements you can actually see, work with, and hold.

I just looked again at the archives of 2011 and 2012 and I remember how much I miss that time when everyone was here! Look at the December 2012 PTQ! Out of the first 99 elements that people care about and can actually see, what have we got to a satisfactory level (GA or above) that wasn't there before? Lanthanum? Okay, but not that important. Thulium? Even less important. Polonium? Cool, but the article isn't really quite GA-class (it's really a B now): we need to fix polonium and radium especially among the secondary radioelements. Neptunium? Okay, but again not that important. Seriously, the only important thing we actually got to GA (and now approaching FA) is thorium. I suppose the superheavy spamming would have been necessary eventually, but...

At least I have nominated the important iron, gallium, and indium, that are awaiting a reviewer, so things do not look quite as terrible. But really, while the table looks good because of the template-ish synthetic "virtual elements" no one cares about, the important elements are just being neglected. Is it that no one dares to do things like arsenic outside a collaboration? That is so sad, but so understandable given the amount of time we all have! (Already thorium takes up so much of my WP time, working alone and following R8R's wonderful suggestions.)

It really makes me sad that every day we don't work on sodium, in the hope that someone can take it to FA later, to leave an alkali metal to have one missing representative of each group for future editors, is a day when readers are stuck with a lame article. Look at all the elements and groups people learn the chemistry of in high school: those would be the first 30 elements, all of the s-block (except Fr and Ra), all of the halogens (except At), silver, and all of group 14. To this we have to add the king of metals, gold, and the arsenic that everyone's heard of. Look how many of them we fail to deliver on! Boron, carbon, nitrogen, sodium, magnesium, aluminium, silicon, phosphorus, sulfur, chlorine, calcium, arsenic, bromine, strontium, silver, tin, iodine, and gold all await a helping hand. And apart from some lanthanides (which would be almost as cookie-cutter as the superheavies, and be just as useful to the average reader), and the radioactive polonium and radium (which, outside history, aren't very important), these eighteen make up all the natural elements that are not of satisfactory quality.

Yes, I know I have complained a lot about things like hafnium and ruthenium (at least, not till I fixed the latter) having lame chemistry sections. But you know what? The average reader isn't looking for that. I would add it of course, but the fixing of our current GAs is not so urgent a priority, except in cases of clearly undeserved GA status (boron, carbon, thallium, polonium). (I consider it "undeserved status" when you can't get it to actual GA status in one day. Selenium and tellurium have some problems, but nothing you couldn't fix very quickly.)

I'm sorry, R8R, but I just can't be convinced by you about this while nitrogen remains a terrible article. I can't look at this without feeling that I have a WP duty to do as much as I can about this, and to maximise the WP time I have for it.

Look how long it took to get fluorine to FA. I can't possibly live to do that for every element at our current rates. But all-GA is possible. Once there is a precedent (Pb, Th) of bringing old GAs to FA after a long break, when you are not the sole author (or perhaps not even an author – for that I'd get my dear tungsten, or beautiful, white palladium) – once all of the table is satisfactory for the general reader – then we can start thinking about making all of it satisfactory for the advanced, in-the-field reader as well.

At least, that's what I think.

But I can't possibly do all of it myself within a reasonable span of time. Double sharp (talk) 16:17, 23 July 2016 (UTC)


 * A message well delivered.
 * I see your point. I just think that if I work on an article, I want to make most of it and don't want to go for weaker GA (and stronger GAs are not far from promotion to FAs). That's what I find interesting to do and to help with. Opinions may vary, but it's okay, isn't it.--R8R (talk) 19:45, 23 July 2016 (UTC)
 * Thank you! Double sharp (talk) 06:45, 24 July 2016 (UTC)

I realise, also, that the idea of getting a set of articles done is a good motivator. This is how the actinides got finished, as well as many of the transition metals (although that stopped before the last few important ones). Now consider: there are 31 transition metals in the table that people care about, from group 3 of scandium, yttrium, lanthanum, and actinium to group 12 of zinc, cadmium, and mercury. (I use lanthanum here because it gets more views than lutetium.) How many of them are satisfactory now? Almost all of them! The exceptions are iron (which is at GAN, so I won't count it), silver, and gold. That's 29 out of 31 in 2016, while in 2007 we had four. Not bad for a decade! Now let's try something that will be even more useful.

Consider the p-block, minus the noble gases (which chemically are not so interesting and anyway are a featured topic already). This is one of the weakest regions in the table. Since many of them are important nonmetals, they need a quite different style of writing from the metals which we have so many good articles for. (The exceptions – sodium, magnesium, calcium, and strontium – are in the s-block, and have reasonably good models to follow in potassium and barium. Radium needs to be thought of from a history-first perspective, instead of a properties-first perspective.)

Why don't we fix them all, in the same sort of drive that the transition metals were? There are slightly fewer articles to worry about here (25), and many are done already. It's just the most important ones that are left:

We are now at 11/25, or almost halfway. Maybe in less than a decade we can be at 25/25! (And regarding polonium, it has to be done at some point, but I wouldn't make it a priority.) And even though these are mostly scary elements, they have the advantage that Greenwood and Earnshaw usually devote a whole chapter to them. Already there are single chapters on B, C, N, Si, P, and S that can be mined for information.

I'm not saying that the okay articles like selenium and tellurium don't need work. There are still things that could be improved there. But it would help the reader more to fix the ones that are not okay. I'm not trying to say that we shouldn't FA lead now and tin later, being among the seven metals of antiquity. That is great, of course! I'm quite happy to be contributing to the Pb FA. We need some featured articles to be happening. But we also should have a torrent of good articles flowing through like we had in 2011 and 2012. It will be more difficult to build it up this way with fewer people around, but I hope it can still work.

I would not prefer to see this table responded to with "oh, okay, I'll reserve iodine, and you can do something else". No, I'd prefer something like "hello, I'm trying iodine, but I ran into a few problems, could you help?" That's how potassium and barium got done, after all. Why would it not work again? Double sharp (talk) 06:45, 24 July 2016 (UTC)
 * As a starting point for this, I fixed the worst section of thallium (chemistry), so now I think I can dare to call it a true GA (most of the rest was satisfactory, I think). Now we are at 12/25. Maybe doing these small fixes will help motivate people to aim for the truly scary ones. Double sharp (talk) 08:02, 24 July 2016 (UTC)

I would still suggest, finally, that while we should ideally have one or two FA pushes going on at any time (we have Th for now, to be followed immediately by a return to Pb), we should also try to have a reasonably steady flow of stable-element non-lanthanide GAs pushing through (hopefully at least one at a time; lanthanides and superheavies are nice-to-have extras), to have the best of both worlds. And for now, we are actually somewhat succeeding in doing that, with two in progress-FAs and three GAs awaiting review. We just need to continue having it like that; instead of the blankness of 2015, instead of the hyperactivity of 2011 and 2012, we can just keep going slowly at a constant rate towards progress. Double sharp (talk) 08:36, 24 July 2016 (UTC)

Really final post: I'm not opposed to doing lanthanides, of course. It's just that they for the most part are uninteresting and not in the public eye (okay, Ce and Nd may be exceptions; I planned to do the first four, getting these and Pr as well, finishing the early cerium-group lanthanides). But let's not only do that. Double sharp (talk) 05:47, 25 July 2016 (UTC)

Nomination for deletion of Template:Chemical elements named after places, scientists
Template:Chemical elements named after places and Template:Chemical elements named after scientists have been nominated for deletion. You are invited to comment on the discussion at the template's entry on the Templates for discussion page. -DePiep (talk) 15:13, 26 June 2016 (UTC)
 * So they have been deleted. The TfD conclusion is worth reading, a good understanding of "not a defining property" as a navbox base. OK so far.
 * Sadly, after deletion editor started adding surrogate navbox links to "See also" sections (eg [Cu]). I reverted, but this is getting into an WP:EDITWAR, so I do not rv again for the moment. It looks like all navbox-affected elements are targeted, possibly FA articles.
 * I propose & request that we squash these edits (per TfD outcome). -DePiep (talk) 21:17, 18 July 2016 (UTC)
 * I have nothing to say but to express support.--R8R (talk) 21:21, 18 July 2016 (UTC)
 * mind dropping a word so we have a dialogue on the issue?--R8R (talk) 16:24, 19 July 2016 (UTC)
 * Maybe it was too hasty to add the "see also" links, and I would probably not have reverted if it was done by anybody but DePiep (we have a history at ANI etc.). That said, I think the element articles are missing links to comparing data (I know every element article has two periodic tables (in infobox and as navbar)). I still thinks that the links I added are relevant, but after recalibration I thin a much better idea is to add Navbox elements data combined with the navbox version of Sidebar periodic table. And it would be to link (the list of...) in the text at the point its mentioned that the element is named after place/person. Christian75 (talk) 14:03, 20 July 2016 (UTC)
 * re writing "(we have a history at ANI etc.)": please strike it asap -- not an argument at all. -DePiep (talk) 23:16, 22 July 2016 (UTC) ping
 * I think such lists are not really relevant and I'll try to explain my point. Of course, each element has a name and that name comes from something. But is this a big deal? Likewise, every element has density of the free state, color, atomic number, etc., and we don't make lists for dense/green/big-numbered elements. Are names particularly important? I think so not. For example, a non-existent category Category:Elements discovered in the 1940s makes a lot more sense to me, as this reflects an important part of history of the elements and development of chemical knowledge. Having a name after something doesn't even say anything neither from theoretical nor practical perspective. I think it's a stat easy to make and that's why some people like it, but it's nearly pointless to me, as "being named after a place" is not really a category of any practical significance. (Not to say there's been a discussion on that already.)--R8R (talk) 09:21, 23 July 2016 (UTC)


 * This is the same argument that concluded the TfD into deletion. The See also section is not a place for indisciminate listing, just as a navbox is not. -DePiep (talk) 12:21, 24 July 2016 (UTC)
 * Given the consensus here, I've reverted Christian75's edits. Double sharp (talk) 07:13, 25 July 2016 (UTC)

Periodic Law & Periodic trends
Please contribute to the discussion about merging Periodic Law and Periodic trends. I just now started the discussion, but the articles were tagged User:Suruena by back in February.

As an aside, I wondered whether I should start the discussion on one of the article talk pages or here. If you have any suggestions that might guide future decisions, please let me know.

YBG (talk) 08:12, 27 July 2016 (UTC)

Biological role of the elements
It so happens that we have some articles on them: see Category:Biology and pharmacology of chemical elements. Included are Na, Mg, K, Ca, Fe, Cu, As, Se, and I. Double sharp (talk) 07:47, 31 July 2016 (UTC)

The reason why I mention this is that it's the biological role thing that makes me afraid of doing most of the first few rows, because they are so important. I only dared to do Fe because Greenwood has a large section (25.3.5) about it, talking about haemoglobin and myoglobin, cytochromes, and iron-sulfur proteins. (And even now I think the current biology section is inadequate and I should edit it. The chemistry is okay, but at this point I'm expecting that as a non-negotiable matter of course for anything I do here.) I don't feel so scared about things like Pb or Th because they poison you. They're not meant to be there. I also don't feel so scared about N because it is everywhere. But if we talk about the ones in the middle – I get frightened away from doing them. I know I talk a lot about how we should work on the most important elements, but I can perfectly see why we don't. Just like all over Wikipedia, the easier ones tend to be done first, and they are unfortunately also the ones readers are not so interested in. So, if you like, you can think of these resources as ways to help yourself see the all-blue table without needing to achieve immortality. And this is why I still explicitly said that the actinide-and-transactinide-spamming (almost done) and lanthanide-spamming (halfway-through) initiatives were useful – relegated to the end of Greenwood and Earnshaw, they nevertheless, step by little step, make the table easier to look at, and highlight how the important ones are left, and cannot be run away from. And as the choices whittle down, I hope that there is some way to get them done – especially for the big ones that Greenwood and Earnshaw devotes whole chapters to: H (FA), B (GA), C (GA), N, O (FA), Si, P, S (basically, CHNOPS + B and Si). Double sharp (talk) 08:14, 31 July 2016 (UTC)

get rid of the A-class?
It is a little silly IMHO now. It is on the level of GA and FA, where you need reviewers, but we don't really have a reviewing system for it anymore. Double sharp (talk) 04:11, 30 July 2016 (UTC)
 * ✅ Double sharp (talk) 04:14, 30 July 2016 (UTC)
 * Similarly, killed the B+-class; it's just not used enough to actually be useful (and even when it was used a lot, it tended to just mean "almost ready for GA"). Double sharp (talk) 04:38, 30 July 2016 (UTC)
 * Good riddance. Will automatically update? Periodic table by article quality must be manually adjusted. YBG (talk) 05:25, 30 July 2016 (UTC)
 * I already did (including the PTQ image), but you may not see it immediately due to caching. Double sharp (talk) 06:01, 30 July 2016 (UTC)
 * Ah, how amusing it is that in 2011 we had an expanded class-quality scale, and now our wikitext PTQ has only FA, GA, B, C, and Start! Double sharp (talk) 09:00, 31 July 2016 (UTC)
 * The B+ class was a local invention, and so not that important. However, A-class is a serious step in the ladder. By removing it, it is impossible to use that intermediate level. IOW, an improvement above B-class by then actually is a double step, having to skip A-class. In short, looks a bit weird to have an incomplete classification scheme. -DePiep (talk) 10:10, 1 August 2016 (UTC)
 * The issue with A-class is that it requires a full-scale review of the content by those with the necessary knowledge. But we do not have a formal process, because we don't have enough people, so our prior A-class was meaningless. We need to ask ourselves: why do we need an A-class? The obvious reason is that content issues may not be grappled with enough at GA and FA, which tend to be more based on prose. But I find we tend to take a very decentralised approach to it, because we just don't have enough people now to do a full-scale one with everyone pitching in. So I tend to just ask someone who I think would know the stuff, or do lots of reading until I can look objectively to an element. So I do not think the A-class really helps us. Double sharp (talk) 13:39, 1 August 2016 (UTC)
 * You're following the premise that a review must be held for a high rating. I don't think it's necessary. We can rate articles in any manner we want (some projects don't even follow the regular A/B/C/Start criteria). Except GA and FA statuses are defined outside of our project; but we could ignore these if we wanted. I didn't like how I went to bed one day and checked during the morning the next day, and the discussion has been completed.
 * As for A-class articles, we could use them in a manner similar to the Bplus-class (which is also gone; why? If it's not used, it doesn't mean it won't be. "Almost ready for GA" is a valid purpose to have that rating); this doesn't require a special preview. Or just FA-worthy articles that need some cleaning before FAC and possibly one or two minor points missing (which is generally what I think of this class as); this doesn't require a special review if we agree so. You are capable of giving that rating; I am; some others are.--R8R (talk) 22:53, 3 August 2016 (UTC)
 * I rated all those As and B+s that I downgraded to GA and B, precisely because I am not sure of my own old ratings of them. I am just not confident enough to unilaterally declare it is so when others could disagree – for example, I still think alkali metal needs still more chemistry (reaction with group 13 elements, as well as a better explanation of what exactly is going on with them as well as Ca, Sr, Ba, Eu, Yb in ammonia solution). I know you were okay with the current levels but Axiosaurus wasn't, so I tend to give everything the worst rating I can see someone giving. Note also how for Bk PR we had one person saying it was very close to FA and another saying it had too much info and read like a technical work (not that I think this is a bad thing for Bk, though I think it would be a bad thing for U, or, horror of horrors, my future FA targets nitrogen and gold). I think by the time we get to this sort of level, we need to have many pairs of eyes looking. Double sharp (talk) 06:27, 4 August 2016 (UTC)

Ideally yes, many views would be great and a formal procedure would be great. As a small project, however, we seemingly can't sustain such a procedure. We're left with the best thing we can do but not necessarily abandon the ehole idea. For example, fluorine has been an A-class article for a long time and that rating was great (I don't remember if there was a sort of A-class review). That article alone provides a great reason to have that rating.--R8R (talk) 09:43, 4 August 2016 (UTC)
 * The A-Class was reasoned and added with this quote

Lanthanum-138 (talk | contribs)‎. . (5,604 bytes) (-1)‎. . (I realise I am not supposed to do an A-class rating myself, but this has been pulled through 2 FACs, 1 GAN and 2 PRs, and there were a lot of support votes, and expert knowledge is indeed now needed to tweak the article) --Stone (talk) 11:51, 4 August 2016 (UTC)
 * Yes, well, in that case we had two FACs, one GAN, and two PRs, so clearly there were enough eyes looking. I do not think there were enough for hassium or neptunium, for example. (Besides, that was five years ago, when I was new to this project. I certainly do not hold all the same views now!) I don't mind having A-class ratings as long as it is substantiated to that level. But I don't think we currently have an article that would justify it, although we could later. Double sharp (talk) 13:45, 4 August 2016 (UTC)
 * I'm absolutely fine with that. Having zero A-class articles and abandoning the whole rating are two different things; the first one is okay on me.--R8R (talk) 12:33, 5 August 2016 (UTC)
 * OK, thank you! Double sharp (talk) 15:14, 5 August 2016 (UTC)

Heavy metal (chemical element): Once more into the breach
As the headline says, I've nominated this article again. Thanks to User:YBG for thought-provoking commentary, following the first unsuccessful nomination. Sandbh (talk) 02:22, 7 August 2016 (UTC)

DePiep: Published at last
Today I saw a book in my local bookstore called The Periodic Table in Minutes (2016, Dan Green). Page 169 shows the Benfey periodic table as per User:DePiep's image, here. The last page of the book has the picture credits and the second to last entry says, "169: DePiep/Wikimedia". Sandbh (talk) 11:41, 14 August 2016 (UTC)


 * Wow, congratulations!--R8R (talk) 15:16, 14 August 2016 (UTC)

Oxidation state +10?: Maybe so
In the PtO42+ oxide cation, here. Sandbh (talk) 12:38, 17 August 2016 (UTC)


 * I will notice this isn't the first time a possibility of [PtXO4]2+ has been suggested. See here, for example (it's in Russian; I've had it bookmarked on my laptop for a while); the paper dates back to 1999. It, similarly to the newer paper, suggests that there could be an unstable platinum(X) tetraoxo- dication (it actually quotes a different article, which I can't find despite having a citation).--R8R (talk) 13:58, 17 August 2016 (UTC)

A flux of steam
In, it says:
 * Lavoisier produced hydrogen for his experiments on mass conservation by reacting a flux of steam with metallic iron through an incandescent iron tube heated in a fire.

(emphasis added) Flux should be linked. Is the proper target Flux (metallurgy)? YBG (talk) 01:58, 26 August 2016 (UTC)

Hydrogen adopts alkali metal position
I think I missed this one. Sandbh (talk) 05:32, 27 August 2016 (UTC)

Tongue-in-cheek colour scheme
Shamelessly appropriated from feline1 (here): a colour scheme that reflected the actual colours of the elements. We'd have a gradient of greyness, a colour-fiesta on the right, and some heartbreakingly beautiful treasures like Au, Cu, Os, Ta, Cs, Eu, Yb, Ca, Sr, Ba...although what to do with elements like At, Fr, and Fm++ which have never been seen? ^_^ Double sharp (talk) 06:12, 30 August 2016 (UTC)
 * Obviously need to have white font color on a white background. If its never been seen, it should never be seen. YBG (talk) 06:15, 30 August 2016 (UTC)
 * I am very tempted to make this colour scheme happen, with the slight problem that I suspect many of the metal colours would be impossible to show up properly as solid colours...how to capture Hg reflections... Double sharp (talk) 06:18, 30 August 2016 (UTC)
 * Any chance to connect it up to a web cam to simulate the shiny, mirror-like surface? YBG (talk) 06:21, 30 August 2016 (UTC)
 * Yes, maybe each background is instead a close-up photo of a homogeneous sample of the element. (Presumably we would dispense with this for the colourless gases – H, He, N, O, Ne, Ar, Kr, Xe, Rn – and just have a transparent background.) You'd also have sparkles (1:34).
 * As for elements that have never been seen, we could take them off the table entirely. With the inclusion of some of the more dangerous radioactives we could actually almost succeed in producing a virtual periodic table where each cell was made of its own element without dying! (Though I suppose we could already have one today – you'd presumably have empty transparent cubes for the radioactive ones. I would love to have Th and U represented, but somehow I don't think many people will be too happy with that.) Double sharp (talk) 09:48, 30 August 2016 (UTC)