Non-empirical calculations of the electronic structures of 6a-thiothiophthen and related molecules

Abstract

Computations of the ground-state wavefunctions for the title compound, and its 1 -oxa-, 1,6-dioxa-, and 1-azaderivatives, are described. A bond energy analysis shows that the molecules have little resonance energy. The title compounds shows two lone pair orbitals at the centre sulphur atom, but the 3d orbitals are not heavily involved in the bonding in this series of molecules. The photoelectron spectra are analysed and compared with the π-isoelectronic molecule naphthalene.