https://doi.org/10.1351/goldbook.M04062
The number of possible orientations, calculated as \(2\ S+1\), of the spin @[email protected] corresponding to a given total spin quantum number (\(S\)), for the same spatial electronic wavefunction. A state of singlet multiplicity has \(S=0\) and \(2\ S+1=1\). A @[email protected] has \(S=\frac{1}{2}\), \(2\ S+1=2\), etc. Note that when \(S>L\) (the total orbital @[email protected] possible) there are only \(2\ L+1\) orientations of total @[email protected] possible.