Talk:Angular momentum coupling

LS Coupling = Spin-Orbit Coupling?

LS Coupling and Spin-Orbit coupling are different things. LS Coupling is a residual electrostatic effect that takes into account the non-radial part of the electron-electron repulsion - the states are split according to their spin configuration (symmetric or antisymmetric). So it should say Spin-Orbit, not LS - WeeJock

From PNA/Physics

• Angular momentum coupling - this article is a mess right now. Passw0rd 21:25, 14 Dec 2004 (UTC)

I totally agree. The article is totally confused on what spin-orbit coupling is. LS and jj couplings are not spin-orbit coupling - they are techniques for giving quantum numbers to multi electron systems. Spin-orbit coupling is a relativistic effect from the dirac equation. After my exams I might do something about this. LeBofSportif 09:07, 24 May 2006 (UTC)

Wording change to "break the degeneracy"?"

I think that the following sentence should be edited: "One of its effects is to degenerate the energy level for the parallel and anti parallel cases, of the spin and the Angular momentum." Instead of degenerate, I think "break the degeneracy" would be more appropiate, because without the orbital considerations the energies ofthe spin and spin down states would be the same. The coupling therefore is what breaks the degeneracy.

Hi anonymous! Welcome to Wikipedia - I noticed that you've made a few new articles already, such as internal conversion coefficient - they're really great stubs. Please feel free to make the changes to the articles (like this one) as you see fit - if you look at the page history, nobody has touched this page since almost 2 months ago. I'm glad there's someone interested in angular momentum coupling - these pages on Wikipedia can be greatly improved with your help. --HappyCamper 11:59, 23 Jun 2005 (UTC)

Wording changes

Yes, I was thinking about this and realized I had been sloppy in describing the way in which the spin-orbit effect breaks the degeneracy in the nuclear shell model; I was trying to say that if you don't use the Nilsson model, which further lifts the degeneracy due to removal of nuclear symmetry when the nucleus is deformed, then each orbital's nucleons are degenerate with respect to one another.

(Added by 24.84.203.193 23 Jun 2005, 21:35 (PDT)

Rydberg vs Russell-Saunders States

The Rydberg series suggest the existence of atomic states which are referred to as "Rydberg states" or "Russell-Saunders states". Pauling uses Russell-Saunders state. Herzberg in his Lindau lecture mentions Rydberg states. These terms might differ somewhat semantically but I used Rydberg states which is probably older and more consistent with the use of "term symbol." --Jbergquist (talk) 21:30, 8 September 2009 (UTC)

I don't believe these two names are synonymous. Rydberg states are states in which an orbital outside the valence shell is occupied (e.g. Li(1s²ns) with n = 3, 4, 5, ...). Russell-Saunders states are states with LS-coupling, defined for states with two or more electrons outside a closed shell. Dirac66 (talk) 02:50, 9 September 2009 (UTC)

Spin-orbit vs LS coupling

Spin-Orbit is not the same as LS coupling. The problem with this page is that there is not a clear distinction between angular momentum coupling and spin-orbit coupling. LS coupling is a change of base that you have to perform in order to diagonalize your Hamiltonian H when angular momentum L and spin S are no longer conserved (do not commute with H). Spin-orbit is a relativistic effect that couples motion, potential and spin of particle, it is a specific term in the Hamiltonian. Now you may need to do LS coupling to obtain the (perturbative) eigenfunctions of your system when the spin-orbit term is added, but you could also need to do LS coupling if you add other electron-electron interactions. --MaoGo (talk) 12:54, 7 February 2018 (UTC)

Momenta

Surely “moments” ? Or is this quanyum argot? Jabberwoch (talk) 01:14, 28 October 2021 (UTC)

Momenta is the Latin neuter plural. The singular is momentum and the plural is momenta. Another example is quantum and quanta. Dirac66 (talk) 02:26, 28 October 2021 (UTC)