Electronic and structural properties of the oxygen vacancy in BaTiO3

Abstract

The electronic and structural properties of the oxygen vacancy (VO) in cubic BaTiO3 are studied using first-principles calculations based on a hybrid Hartree–Fock density functional approach. Our calculations identify the double shallow donor behavior of VO, indicating its contribution to the n-type conductivity. In addition, a metastable configuration is found, which shows an off-symmetric atomic structure around VO in conjunction with deep localized electronic states in the band gap. Based on the identified characteristics of VO, the previous experimental and theoretical findings are explained.