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Actually how do the articles in the See also section Potential energy surface, Diabatic, Conical intersection, Avoided crossing,Vibronic coupling relate to the Jahn-Teller effect?V8rik 7 July 2005 15:02 (UTC)

A complex may be found at a minimum of the potential energy surface after undergoing a Jahn Teller distortion process. Most of the other references are related to this, but I'm still not sure about the conical intersection and vibronic coulping. -- Rune Welsh ταλκ July 7, 2005 15:16 (UTC)
Check this article [1] if you can. It explains the relationship between conical intersection and Jahn-Teller effects quite nicely. -- Rune Welsh ταλκ July 7, 2005 16:15 (UTC)
I have introduced those links because they are evident to me. A Jahn-Teller effect occurs when two potential energy surfaces are crossing for some symmetry reason. This is just the case where the Born-Oppenheimer approximation fails, i.e. when the vibronic coupling cannot be neglected. In such case the Diabatic representation is the best one. This of course corresponds also to a conical intersection. But I am not a specialist and I would not like to write to much stupidity about this. That's the reason why I have not commented all this that much.

octahedral complex

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the Jahn-Teller effect is a pretty advanced topic in chemistry and a reader would really benefit from some groundwork, octahedral complex would be preferable over octahedral complex. See also the AXE method, most molecular geometries are still missing. V8rik 20:07, 12 July 2005 (UTC)[reply]

preservation of inversion center

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I'm pretty new to this Wiki editting but I thought I'd start here. The Jahn-Teller effect preserves the inversion center, if present in the 'original' complex. Source is “Inorganic Chemistry” 4th ed., Huheey, Keiter, Keiter (HKK), pages 499-455. I doubt this source helps as it's not available online for viewing. I think it'd be important to add this preservation in the article. Heymon32 05:50, 6 February 2007 (UTC)[reply]

OK, I added a sentence to that effect. The general rule in Wikipedia is: Be bold. If you want to make a sensible change, go for it! Chris 09:04, 6 February 2007 (UTC)[reply]

organic chemistry

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second order JT sentence makes no sense — Preceding unsigned comment added by 134.76.64.168 (talk) 17:00, 27 November 2013 (UTC)[reply]

Illustration of Cu(H2O)5

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Actually, the Jahn-Teller effect does does not present in such molecule and it's written in article [2], wrom where the picture is taken. Why does it illustrate an article about Jahn-Teller effect? — Preceding unsigned comment added by 195.19.236.78 (talk) 09:30, 18 May 2016 (UTC)[reply]

The J-T effect explains the nonequal Cu-O distances in Cu(II)L6 complexes. If you have a better example than the one indicated, please suggest it.--Smokefoot (talk) 11:52, 18 May 2016 (UTC)[reply]
(edit conflict with Smokefoot) Good point, 195.19.236.78. File:Cu water.png shows the structure of Cu2+ in aqueous solution, whereas File:Hexaaquacopper(II)-3D-balls.png shows the structure of [Cu(OH2)6]2+ in various crystalline environments. I imagine the editor who originally added the [Cu(OH2)5]2+ image wanted to point out that the Jahn-Teller-distorted [Cu(OH2)6]2+ ion is not actually present in aqueous solution. We could certainly make this point clearer in the article. --Ben (talk) 11:56, 18 May 2016 (UTC)[reply]
Well I encourage you to edit for clarity. So what you are saying is that because of the J-T effect, few [CuL6]2+ ions exist in solution, and then in the solid state, one has to worry about packing forces, etc. In Greenwood and Earnshaw, they refer to J-T several times but are most confident in assigning it in binary solids Mn2O3 and MnF3. It is an interesting concept, but possibly over-emphasized. Not sure why we torture students with it.--Smokefoot (talk) 12:49, 18 May 2016 (UTC)[reply]
I've found the most relevant review I could (Persson, Pure Appl. Chem. 2010 82, 1901) and described its conclusions (or lack thereof) on the structure of Cu2+ in aqueous solution very briefly in the caption of File:Hexaaquacopper(II)-3D-balls.png. I've moved the offending image to Metal ions in aqueous solution#Transition metals and group 12 metals. Hope this clears things up. --Ben (talk) 10:52, 19 May 2016 (UTC)[reply]

Changes to increase coverage of existing page

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Several members of the International Steering Committee of the Symposia on the Jahn-Teller effect conference series felt that the current Wikipedia page did not give full coverage of this topic. We have worked together to improve the current page.Janette Dunn (talk) 10:33, 16 December 2016 (UTC)[reply]

Also, we tried to contact the wikipedia editors about a draft we had prepared and to query about the best (and polite) way to update the page and we were told to directly edit the current entry.P garcia fernandez (talk) 13:19, 16 December 2016 (UTC)[reply]

Active editors of chemistry articles can be found at Wikipedia_talk:WikiProject_Chemistry and that would be your best port of call for discussing large changes like this one. It's very welcome to have the experts of a field helping with an article, my only criticism would be that the article is now exceedingly technical. Wikipedia is an encyclopedic reference and as far as is possible we try to make it accessible to lay readers. It may well be necessary to add a section which explains the phenomenon more simply (i.e. something an undergrad might be able to understand). --Project Osprey (talk) 22:43, 16 December 2016 (UTC)[reply]

"the electronic and vibrational states"

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First paragraph in the theory section we read that its about the symmetry of the engaged "electronic and vibrational states" this contradicts one of the earlier statements that the distortion is strictly not a normal mode of vibration but rather some nuclear motion on the split(ing) PES. Could that gap of argumentation be filled? --91.115.119.223 (talk) 05:46, 7 July 2017 (UTC).[reply]

== Error in Reference "" A reference concerning the first JT treatment using computed energy surfaces has an error. "J. of Chem. Phys." instead of "J. Chem. Phys." Ordinary access to correct this doesn't work. How can this be corrected?

MagnaGraecia (talk) 01:11, 9 September 2018 (UTC)Magna Graecia[reply]

d9 configuration for Cu(II) ?

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It seems to me that Cu(II) is a d7 ion. The atomic electronic configuration of the Cobalt (Z=27) is (Ar) 4s2 3d7 by following the Klechkowski rule, then for the Co(II) the electrons are in first withdraw from the 4s2 to obtain (Ar) 4s0 3d7 — Preceding unsigned comment added by MakeUsSeeEarth (talkcontribs) 11:07, 16 November 2019 (UTC)[reply]

Good point but the funny thing that happens with the first row transition metals is that, upon formation of complexes, the 3d level dips below the energy of the 4s level. So basically all valence electrons are d-electrons. This is the reason we call copper(I), d10, like Ni(0). Analogous arithmetic applies to 4d and 5d metals.--Smokefoot (talk) 12:43, 16 November 2019 (UTC)[reply]

Mention of spectroscopy textbook by Bunker and Jensen.

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I do not understand how the mention of Section 13.4 spectroscopy textbook by Bunker and Jensen adds anything of value to the lead section of this entry. The book is already mentioned in the reference section and I think that should be enough. The line: "The Jahn–Teller effect, and the related Renner–Teller effect, are discussed in Section 13.4 of the spectroscopy textbook by Bunker and Jensen.", should be deleted from the lead section. — Preceding unsigned comment added by Rock-Bottom007 (talkcontribs) 08:15, 11 May 2022 (UTC)[reply]