A constrained variational route to Pauling's electronegativity values

Abstract

Pauling's idea of estimating electronegativities of atoms by using bond-dissociation energy data and the idea of ionic-covalent resonance interaction are examined. Effective Hamiltonian for the perfectly covalent and perfectly ionic structures are defined and a constrained variational recipe to obtain their respective ground state energies suggested. These energies, together with the actual energy of the ground state of a diatom are used to obtain an estimate of the ionic-covalent interaction energy at different values of R. It naturally leads to an estimate of the electronegativity difference ΔX between the atoms at various distances.