Ab initio Hartree-Fock study of tetragonal and cubic phases of zirconium dioxide

The structural and electronic properties of cubic and tetragonal zirconia (ZrO2) are studied using a periodic ab initio Hartree-Fock method. Only valence electrons are treated explicitly, while effective core potentials are used for describing core electrons. The equilibrium geometries and elastic properties of the two phases are studied, and the mechanism of phase transition is discussed, with possible effects of applied pressure being taken into consideration. The analysis of the electronic structure shows appreciable departure from a purely ionic type of bond.