The structural and electronic properties of fully relaxed CaTiO3 oxygen-vacancies (001) surface with CaO and TiO2 terminations were investigated by first-principles plane waves ultrasoft pseudopotential method based on local density approximation. The present results show that the direction and the magnitudes of the atomic relaxations for oxygen-vacancies surface were different from that of the perfect surface. Compared with the TiO2-terminated oxygen-vacancy surface, the CaO-terminated oxygen-vacancy surface were likely to be observed in oxygen environment conditions. Much different from the perfect surface, the oxygen-vacancy surface becomes metallic caused by some states in the conduction band were lowered and pulled down in the band-gap region.

First-Principles Study of CaTiO3 Oxygen-Vacancies (001) Surface. H.Wang, G.Wang, X.Wei, J.Cui: Physica B, 2012, 407[19], 3970–4