A new version of the program TSYM generating relativistic molecular symmetry orbitals for finite double point groups Original Research Article

A revised and extended version of the program TSYM is presented. Relativistic symmetry-adapted basis systems for molecular calculations are constructed from atomic orbitals according to the LCAO method. The molecular symmetry group can be one of 45 finite double point groups. The algorithm based on the projection operator formalism automatically ensures the linear independence of the symmetry orbitals. Time reversal invariance, taken into account as an additional symmetry property, provides further information on the structure of matrix elements.