41.5.2 Options for spin-orbit calculations

Some options can be set using the OPTION directive (in any order)

OPTIONS [,WIGNER=value][,HLSTRANS=value][,MATEL=value]

where

WIGNER

This option determines whether the Wigner-Eckart theorem should be used when the SO matrix is determined. WIGNER=1 (default) uses the theorem, WIGNER=0 calculates each SO matrix element individually. This option is needed for test purposes only.

HLSTRANS

This option determines whether a SO matrix calculation should be performed in the not spin-symmetry adapted basis set (HLSTRANS=0), in the spin-symmetry adapted basis set (HLSTRANS=1, default) or with both basis sets (HLSTRANS=2). At present, symmetry adaption can only be performed for triplet states, where the following notation is used to indicate the symmetry adapted spin functions: $\vert S,M_S\rangle_+ = \frac{1}{\sqrt{2}} (\vert S,M_S\rangle + \vert S,-M_S\rangle)$, $\vert S,M_S\rangle_- = \frac{1}{\sqrt{2}} (\vert S,M_S\rangle - \vert S,-M_S\rangle)$. If only singlet and triplet states are considered, the spin-orbit matrix is blocked according to double-group symmetry and the eigenvalues for each each block are printed separately. In all other cases the HLSTRANS option is ignored.

MATEL

If the entire SO matrix is calculated using HLSMAT, the individual matrix elements are normally not shown. When the option MATEL=1 is given, the individual matrix elements and the contributions of the internal and external configuration classes are printed.