The electronic structure of the tetrasulphur tetranitride dication, S4N42+: an abinitio molecular orbital study

Abstract

Abinitio Hartree–Fock–Slater molecular orbital calculations on the planar tetrasulphur tetranitride dication S4N42+ reveal that it can be described as a fully delocalised 10 π-electron system. Overlap populations for the NS bonds suggest a bond order substantially stronger than in neutral S4N4. The strong uv/visible absorptions observed for S4N42+ at 346 and 262 nm are assigned to nπS → π* and nπN → π* excitations. The Hartree–Fock–Slater π-molecular orbital manifold is discussed in relation to simple HMO concepts.