Ab initio calculations of oxosulfatovanadates

Ab initio restricted Hartree-Fock and multi-configurational self-consistent-held calculations together with second-order perturbation theory have been used to study the geometry, the electron density and the electronic spectrum of VO2SO4-. A bidentate sulfate attachment to vanadium was found to be stable with an O-V-O angle of 72.5 degrees. The calculated spectrum shows bands in reasonable agreement with an experimental spectrum which has been attributed to VO2SO4- Geometry optimizations on (VO2)(2)SO2(SO4)(2)(2-) and (VO)(2)(SO4)(3)(2-) which have been proposed as intermediates in the catalytic cycle, indicate that these compounds are likely to be energetically unstable, if they occur as intermediates at all. (C) Acta Chemica Scandinavica 1996.