Talk:Laporte rule

From Wikipedia, the free encyclopedia

	Laporte rule is part of WikiProject Spectroscopy, an attempt to better organize information in articles related to spectroscopy. If you would like to participate, you can edit the article attached to this page, or visit the project page, where you can join the project and/or contribute to the discussion.
???	This article has not yet received a rating on the quality scale.
???	This article has not yet received a rating on the importance scale.
Comments	Please leave a short summary to explain the ratings and to identify the strengths and weaknesses of the article.

[edit] Comments

I avoid applying those cheesy tags, but you chem wonks must realize that this is unnecessarily opaque. The first things to add are "where g represents..." and "where u represents." In expanding this, just imagine you are explaining this to an intelligent friend of your family. --Wetman 04:16, 16 January 2007 (UTC)

I agree with the above poster. I could probably add a little more information but don't quite have time now.

g = gerade u = ungerade

A designation of g means there is symmetry with respect to an inversion center. That is, if all the atoms (or orbitals) are inverted across the metal center, the resulting compound would look exactly how it did before having inversion applied to it (this includes same orientation in space). A designation of u means otherwise, namely that there is no inversion center.

Moreover, it's very important to note that these rules can be relaxed. This rule basically says that having inversion symmetry "forbids" transitions. Spectroscopy indicates that this isn't the case (citation would probably be HKK Inorganic textbook that I don't have at hand now). Due to asymmetric vibrations, complexes are not perfectly symmetric all the time. This "relaxes" the Laporte rule and allows for transitions that would theoretically be forbidden. 24.7.108.102 08:57, 28 February 2007 (UTC)