Crystal structures of zirconia from first principles and self-consistent tight binding

The origin of the relative stability of the cubic, tetragonal, and monoclin ic phases of zirconia (ZrO2) is investigated. To obtain accurate energies w e adopt a new all-electron bandstructure approach within the local density approximation, based on muffin tin orbitals. We also develop a self-consist ent tight-binding model with which to study the energies for different stru ctures. The tight-binding model enables us to analyze ab initio and experim ental phase stabilities in terms of ionic versus covalent effects, includin g polarization of the anions, and promises to be useful for rapid simulatio n of more complex systems. [S0031-9007(98)07811-9].