Ab initio and classical simulations of defects in SrTiO3

We have performed a computational study of point defects in strontium titanate (SrTiO3) and also examined the antiferrodistortive (AFD) phase transition that occurs in this perovskite material. The simulations include atomic structure optimisations using both empirical and local density approximation (LDA)–plane-wave pseudopotential (PWPP) methods. We report results regarding the relaxed atomic geometries, electron densities of states and Mulliken charges. The results indicate that the oxygen vacancy may have a destabilising influence on the cubic structure.