B. Kralik et al., STRUCTURAL-PROPERTIES AND QUASI-PARTICLE BAND-STRUCTURE OF ZIRCONIA, Physical review. B, Condensed matter, 57(12), 1998, pp. 7027-7036
We report ab initio calculations of the structural and quasiparticle p
roperties of ZrO2, otherwise known as zirconia. The plane-wave pseudop
otential method is used to compute the structural properties of the cu
bic, tetragonal, and monoclinic phases of zirconia. Oxygen vacancies i
n the cubic phase are also studied using a supercell approach. The str
uctural parameters, including all internal degrees of freedom of all p
hases, are relaxed. Excellent agreement is achieved with experiment an
d with other ab initio calculations available. We compute the quasipar
ticle band gaps within Hedin's GW approximation using the method of Hy
bertsen and Louie, and confirm that the quasiparticle approach can be
successfully applied to transition-metal oxides if the core-valence ov
erlap is small. We predict the fundamental gap of pure cubic, tetragon
al, and monoclinic zirconia to be 5.55 eV, 6.40 eV, and 5.42 eV, respe
ctively. Within the GW approximation, the oxygen vacancy state in the
cubic phase is found to be nondegenerate, fully occupied, and well sep
arated from the valence and conduction bands, positioned 2.1 eV below
the conduction band edge.