Talk:Hydrogen anion

"Chemical compounds that formally contain a hydrogen anion are called hydrides" may not be 100% correct: the term refers to many anions (and in principle, cations)
This is a really nice article, but I am skeptical about the desirability for this separate article separate from hydride. HFe(CO)4- is a metal hydride, for sure, and it is not a chemical compound. Or stated more broadly and slightly sarcastically: does every anion that enjoys an existence independent of a charge balancing cation merit two pages - one of the cmpd and one for the anion? In the interstellar medium or in mass spectrometers or whereever, lots of naked anions have been discovered. So AlH4- in THF solution should have a separate page from the salt? Also it is sad taht a reader of hydride must click to this page to get the real picture. Thanks--Smokefoot 12:43, 26 July 2007 (UTC)

Do H− compounds exist or not?
Was "nice article" an irony? I do not see anything nice in a hard confusion which English Wikipedia currently impose on this question. Do true ionic H− compounds exist or not? Or, maybe, more that one sort of a hydrogen anion exists? The lithium hydride article asserts that it is ionic. The hydride article also asserts that ionic hydrides do exist. But hydrogen anion present nothing but speculations about interstellar medium or other low pressure conditions. Incnis Mrsi (talk) 07:07, 22 August 2012 (UTC)
 * The group 1 and 2 hydrides (except BeH2), along with EuH2 and YbH2 are the only ones that you can really think of as ionic. Double sharp (talk) 16:00, 21 August 2016 (UTC)

Atomic orbital or not, electron pair or not…
… but given this composite particle consisting only of a nucleus (hydron) and 2 electrons, these components should be named. Imagine the article helium atom not to mention its two electrons. BTW, H− is the simplest composite anion. Incnis Mrsi (talk) 17:39, 17 March 2013 (UTC)
 * No idea of what the "composite particle" means. Some sort of jargon, I guess. One can be fairly certain that 99.9% of readers will not either, so why immediately begin with jargon and complicated concepts.  Its just H-,  it occurs in outer space, and it is invoked by a thousands of chemists everyday.  I agree completely that the electronic configuration would be relevant to the article, just not the lede. --Smokefoot (talk) 17:58, 17 March 2013 (UTC)
 * Exactly the same thing which explained in Particle, no jargon. If you mind rejected the word “particle” because it is unusual in such context – sorry, the problem is not on my side. You ever have several minutes to think and examine articles before posting the answer. Incnis Mrsi (talk) 18:48, 17 March 2013 (UTC)
 * Well said. --Smokefoot (talk) 19:37, 17 March 2013 (UTC)

Radius of hydride ion
Is there any information about radius of hydride ion? Please help.--G.Kiruthikan (talk) 07:07, 8 November 2014 (UTC)
 * There is not really a single value. It's very squishy! Double sharp (talk) 15:55, 21 August 2016 (UTC)

My edits
I've removed the claim that H- is the dominant light absorber in interstellar space. I can find no reliable source for that - I actually don't find much evidence that it exists in interstellar space, except in molecular clouds in which H2 also exists. I've also edited the rest of the article which mixes up the gaseous anion, with the condensed phase anion (a very different topic!) and with the molecular hydrides (another completely different topic). I have confirmed the assertion that H- is important in the absorption of light in the photosphere of the Sun, but nowhere else. Last August someone else challenged the claim I removed, and so I pulled the trigger on that after a brief search. I have some doubts about the dominance of H-, since for every H- you also have a H+ (in stars' atmospheres) and both are basically free charge carriers and should strongly couple to electromagnetic radiation, but other species also exist there H2+ for example, so I can't claim I understand the basis for the claim well enough to even dispute it. This article is a bit of a mess, especially since it is discussing what I'd consider 3 different things, but I'll leave that to some other intrepid soul.Abitslow (talk) 12:21, 22 June 2016 (UTC)
 * It isn't true that there should be equal numbers of H- and H+ in a stellar atmosphere (unless it is absolutely pure H, which is never true). The "extra" electrons come from elements with lower ionization potentials than H, e.g., the alkalai metals.  The bulk of those will be singly ionized in most of the solar atmosphere, contributing to the nonzero free electron population in that atmosphere, some of which are consumed in making H-.  This is classic stellar atmosphere stuff; I'll see if I can clarify this in the next few days. BSVulturis (talk) 07:08, 4 January 2019 (UTC)

Other hydrogen anions?
Do larger hydrogen anions exist? I wonder in particular about the pentahydrogen anion (H5-), since it would have 6 electrons total, a Hückel number. If this anion were planar and symmetric, it might be stabilized by something similar to aromaticity (but involving s instead of p orbitals). You’d think someone would have tried synthesizing it by now. Since metallic hydrogen exists, polyatomic hydrogen ions aren’t necessarily that far-fetched.LonelyBoy2012 (talk) 04:01, 19 February 2024 (UTC)