First-principles study of the (001) surface of cubic BaZrO3 and BaTiO3

Abstract

First-principles density functional calculations are employed to study the (001) surface of BaZrO3 with both BaO and ZrO2 termination. Surface structure and band structure have been obtained. For the ZrO2-terminated surface, the large displacement of the O atoms in the first layer results in the small surface rumpling. In addition, the largest relaxation appears on the second layer atoms but not on the very first layer ones. The analysis of the structure relaxation parameters reveals that the rumpling of the (001) surface for BaZrO3 with the BaO termination is stronger than that of BaTiO3. The origin of the different surface relaxation behavior between the two materials is discussed. The surface state appears in the band structure of the ZrO2-terminated surface of BaZrO3.