title: The electronic properties of an oxygen vacancy at ZrO(2)-terminated (001) surfaces of a cubic PbZrO(3): computer simulations from the first principles.
abstract: Combining B3PW hybrid exchange-correlation functional within the density functional theory (DFT) and a supercell model, we calculated from the first principles the electronic structure of both ideal PbZrO(3) (001) surface (with ZrO(2)- and PbO-terminations) and a neutral oxygen vacancy also called the F center. The atomic relaxation and electronic density redistributions are discussed. Thermodynamic analysis of pure surfaces indicates that ZrO(2) termination is energetically more favorable than PbO-termination. The O vacancy on the ZrO(2)-surface attracts approximately 0.3 e (0.7 e in the bulk PbZrO(3)), while the remaining electron density from the missing O(2-) ion is localized mostly on atoms nearest to a vacancy. The calculated defect formation energy is smaller than in the bulk which should lead to the vacancy segregation to the surface. Unlike Ti-based perovskites, the vacancy-induced (deep) energy level lies in PbZrO(3) in the middle of the band gap.
authors.affiliation: Institute of Solid State Physics, University of Latvia, 8 Kengaraga Street, Riga, LV-1063, Latvia.
authors.forename: E A
authors.initials: EA
authors.lastname: Kotomin
authors.forename: S
authors.initials: S
authors.lastname: Piskunov
authors.forename: Yu F
authors.initials: YF
authors.lastname: Zhukovskii
authors.forename: R I
authors.initials: RI
authors.lastname: Eglitis
authors.forename: A
authors.initials: A
authors.lastname: Gopejenko
authors.forename: D E
authors.initials: DE
authors.lastname: Ellis