Talk:Inert-pair effect

message: I've removed the following section because it's unsourced and contradicts my understanding of the inert pair effect:
:The inert pair effect can explain why Thallium forms Tl2O while aluminium in the same group forms Al2O3.In aluminium, the electronic configuration is [Ne]3s2 3px1. Because of the screening effect of the 2p electrons, one of the 3s electron can be excited easily to the 3py orbital. So Al mostly exhibits a valency of 3. However in case of Tl, the electronic configuration is [Xe]4f14 5d10  6s2 6px1. Due to the poor screening effect of the 5d orbital, the effective nuclear charge on the 6s electron is high. Hence it cannot be excited to the 6py orbital. So the only unpaired electron remains in the 6px orbital. Hence Thallium exhibits a valency of 1 and forms Tl2O. Similar effect is observed in tin and lead.
"Inert pairs" are stereochemically active so it doesn't make sense to me that they'd simply remain within a perfectly spherical orbital. I'm no expert on this so I could be wrong but the section could do with some rewriting anyway. Blackthirteen 00:01, 5 July 2007 (UTC)
replies: text: The paragraph is wrong, but not for the reason you think it is: if the paragraph were correct, gallium would show a very strong inert pair effect, whereas it shows none at all. The correct explanation involves the effects of special relativity on the mass of the electron: for atoms with a very high nuclear charge, the s-electrons are travelling so fast near the nucleus that the reletivistic increase in mass is non-negligeable, which causes the s-orbitals to shrink and the ionization energy of s-electrons to increase. Physchim62 (talk) 01:02, 2 August 2007 (UTC)
thread_title: Electron remains in s-orbital?

message: Shouldn't this also be a part of Wikiproject:  Chemistry?  Or is there such a thing? RobertAustin 17:32, 26 November 2006 (UTC)
replies: text: Done. Physchim62 (talk) 01:02, 2 August 2007 (UTC)
thread_title:  WikiProjects 

message: This article was automatically assessed because at least one WikiProject had rated the article as stub, and the rating on other projects was brought up to Stub class. BetacommandBot 09:54, 10 November 2007 (UTC)
thread_title:  WikiProject class rating

message: I initially tried a simple expansion but I have ended up with a complete rewrite. I hope no-one is offended. The only questions I have now is why this topic was ever categorised as a relativistic effect--yes Rel effects matter for the heaviest members but looking at the IPs it is obvious that the inert pair effect is not due to higher energy s electrons. Sadly for us all the name is a misnomer--Sidgwick started it in 1927--great man that he was - but he got this one wrong! In terms of the evolution of chemistry the term inert pair effect is probably best viewed as a vestige left over from a palaeolithic past, a bit like the human appendix. sadly for student chemists the simple explanation of the effect is still being taught, so if anyone gets low marks for quoting this  article I'm sorry!  Axiosaurus (talk) 18:13, 9 January 2008 (UTC)
thread_title:  rewrite- sorry 

message: The article Ionization potential doesn't explain the terminology used in the chart.  Is "1st" supposed to mean "first" or something else (I assumed "first" until I saw the rest of the chart)?  Then what is "2st" -- "second"??  "3d" - "3rd","third" or an orbital?  And at last, what does 2d + 3d, used several places in the article, mean at all??  "second plus third" ionization potential or some other specific chemical meaning?  If it's just "first", "second", "third", use consistent terminology all the way through -- if not the words, then e.g. 1st, 2nd, 3rd, or the same set without the superscripts.  If it means something else, explain what it means (either in this article or Ionization potential), or write it out in full, please? - someone who thinks they do know what is meant?  Thanks, —Isaac Dupree(talk) 11:51, 10 July 2008 (UTC)
replies: text: Corrected the typo -  hope that clarifies it! --Axiosaurus (talk) 12:03, 10 July 2008 (UTC)
thread_title:  abbreviation meaning??