Calculating energies and thermodynamic relationships of heteronuclear diatomic molecules at electronegativity equalization

Heteronuclear diatomic molecular electronegativities have been found inadequate when being used to compute molecular quantities from a basis of strictly atomic properties. Pauling originally derived electronegativity as an observed energy difference between the energy of a diatomic molecule AB and its presumed covalent average of AA and BB. From thermodynamics, following Pauling's treatment, a number of fundamental relations that necessarily hold at electronegativity equalization for diatomic molecules, AB, are derived, and a method is proposed for calculating the energies of AB when this condition holds.