A non-empirical SCF-MO study on the conformational properties and asymmetric deformations of dimethyl sulfoxide

Conformational properties of dimethyl sulfoxide (DMSO) have been studied by abinitio molecular orbital method, using various gaussian basis sets. Polarization d functions are essential in reproducing the correct experimental geometry. Barriers to pyramidal inversion on sulfur and Me—S bond rotation have been calculated. The calculated asymmetric S—Me stretching potential indicates that minor intermolecular interactions may cause considerable geometric distortions in the DMSO molecule. These distortions are likely to contribute to the versatile biochemical effects of DMSO.