Atomic Spectroscopic Notation

Forgive me if this has already been discussed. I've been searching and haven't found it. When summing the spin of an atom in the Russell-Saunders coupling scheme, some texts include the spin of an odd nucleon, and some don't. For example, if an atomic energy state is described as ${3}^P_{2}$, this means that the total spin is one, and since $L=1$, $J=S+L=2$. If this is a hydrogen atom, apparently, the spin of the proton is included. Many discussions of this never even bring up the nucleus. When should the spin of an odd nucleon be included?
 

DrClaude

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When should the spin of an odd nucleon be included?
Never. The spin ##S## is the total electron spin.

Nuclear spin only comes into the quantum number ##F##. It is never part of the term symbol itself (the hyperfine state is stated in addition the term symbol, e.g., 2S1/2 ##F=1##).
 

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