A study of sulphur-containing molecules using Hartree-Fock, MP2 and DFT (hybrid) methodologies

The performance is examined of the B3P86 hybrid exchange-correlation function for a set of 21 sulphur-containing molecules. Optimized geometries, harmonic frequencies and mean molecular polarizabilities are presented, and compared with calculations to the Hartree-Fock and MP2 levels of theory, and with appropriate experimental results. The hybrid functional predicts geometries at a level comparable with the MP2 results; harmonic frequencies are in closer agreement with experimental results than either MP2 or Hartree-Fock method; mean molecular polarizabilities predicted by the hybrid functional appear to be substantially closer to experiment than those calculated by either of the other two methods.