ATOMIC VALENCE STATES IN MOLECULAR ORBITAL THEORY

Atomic valence states in simple valence bond and molecular orbital theories of electronic structure have been compared. A basic difference emerges which can be characterised by the presence of one-centre Coulomb terms in the molecular orbital valence state energy. The recognition of this difference is important when performing generalised Hückel calculations: the Coulomb integrals are now given by charge dependent orbital electronegativities, and not the negative of the appropriate ionisation potentials of the kind available in the existing tabulations by Hinze and Jaffé and other authors. The analysis is given in detail for the special case of tetrahedrally coordinated boron and nitrogen, as found in cubic boron nitride. © 1969 Springer-Verlag.