Calculations of interionic potentials in oxides

Calculations of the electronic structure of a pair of O−2 ions in a point-ion lattice are analysed in the manner of a shell model. Induced dipole moments on the highly polarizable ions are explicitly accounted for in fitting the repulsive potential to a Born form. The resulting potential, together with an empirical Mg2+−O2− potential, is used to calculate bulk and defect properties of MgO. The values obtained for bulk dielectric properties using this method are worse than those found from empirical potentials, but defect properties are very similar.