Talk:Term symbol

message: If anyone happens to read this, on the page for Hund's_Rules, it states that they can only be used to determine the ground states, not to order the excited states by energy. However, on the Term_Symbol page it seems to use Hund's Rules for exactly this. I don't know enough about the subject to know where the error lies, but there certainly appears to be an inconsistency at present.
--Westm 06:58, 21 September 2006 (UTC)
thread_title: Hund's rules and excited states

message: I think this page needs to be rewritten, and made clearer and simpler. 
My thesis is on computational and quantum chemistry, and I could honestly not understand and follow the logic of the page, nor find the information that I was looking for.
Doktor Erik (talk) 18:39, 6 June 2008 (UTC)
thread_title:  Needs to be rewritten 

message: The alternative method using group theory as presented is incomplete.  You can only use the rules presented here to work out terms with at most two electrons (or holes) per orbital.  Furthermore, it is unclear wether using group theory for three or more electrons in an orbital is simpler than the method of counting microstates.  In the discussion above, this is referred to as Slater's method.  If this method can indeed be attributed to Slater, it would be great to have a reference.  For example, for a 2p3 configuration
:Γ(1/2) × Γ(1/2)  × Γ(1/2) = Γ(3/2)(A) + 2Γ(1/2)(E)
:P × P × P = S(B) + 3P(A+E) + 2D(E) + F(A).
where A,B,E are the irreducible representations of the S3 permutation group. Since the overall symmetry with respect to this group must be B, the only allowed configurations are 4S, 2D, and 2P. The catch is that assigning the different terms of (Γl)n and (Γs)n to irreducible representations of Sn is still a fairly significant counting problem for n>2. Furthermore, this discussion almost certainly exceeds the scope of Wikipedia. 128.146.35.211 (talk) 22:17, 4 November 2011 (UTC)
replies: text: I have now noted the limitation to two electrons (holes) at the beginning of the section. As you say, the method for 3 or more electrons (holes) is too complex for Wikipedia. We could, however, refer the general case to a suitable reference, if you have one. Dirac66 (talk) 00:23, 5 November 2011 (UTC)
thread_title:  Alternative method using group theory is incomplete 

message: The article says: “S is the total spin quantum number. 2S + 1 is the spin multiplicity: the maximum number of different possible states of J for a given (L, S) combination.”
My concern is with this part  “2S + 1 is the spin multiplicity: the maximum number of different possible states of J for a given (L, S) combination.”
2S + 1 is the maximum number of different possible states of J for a given (L, S) combination only if L is greater or equal to S, i.e. L≥S. Otherwise the maximum number of different possible states of J is 2L+1.
Please see L.D. Landau and E.M. Lifshitz "Quantum Mechanics. Non-relativistic Theory" & 66 "Atomic energy levels" for reference.  — Preceding unsigned comment added by Pauk1234 (talk • contribs) 10:47, 7 February 2016 (UTC)
replies: text: Yes, you are correct, thank you. I had recently made the same correction to the article on Multiplicity (chemistry). I have now corrected this article also. Dirac66 (talk) 13:14, 7 February 2016 (UTC)
thread_title:  Small error in the text