Non-empirical calculations with valence-shell molecular orbitals

Abstract

The method of performing valence-shell molecular orbital calculations published previously is enhanced by the addition of a pseudopotential. This corrects for multi-centre core–valence overlap and prevents collapse of the valence wave function into the core. The method has been implemented in ATMOL3. The method is tested by calculation on Li₂, N₂, CF₄, CBr₄, TiH₃F and MnO^–₄, a comparison being made with all-electron calculations in the same basis.