= Term symbol
{title2=$^{2S+1}L_J$}
{wiki}
In <LS coupling>, an atomic term symbol specifies total electronic <spin> $S$, total <orbital angular momentum> $L$, and total <angular momentum> $J$. The superscript $2S+1$ is the spin multiplicity; the letters $S,P,D,F,\ldots$ denote $L=0,1,2,3,\ldots$. Coupling gives $J=|L-S|,\ldots,L+S$, and a fixed-$J$ level has $2J+1$ magnetic substates before an external field resolves them. For example, $^3P$ has $S=L=1$ and levels $J=0,1,2$, containing $1+3+5=9$ states altogether. A term symbol does not itself specify the radial <electron configuration>.
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