The first-principles study of electronic and optical properties of BGO and BSO scintillators

In this paper we present electronic and optical properties of two important scintillating materials: the Bi4Ge3O12 (BGO) and the Bi4Si3O12 (BSO). These properties were calculated by first-principles, density-functional theory based full potential augmented plane wave method. We discuss the differences between the band structures and optical constants of the BGO and BSO, and analyze the process of absorption of the radiation energy in these materials. Our results indicate that the major part of this energy is absorbed by the O p-electrons and then transferred to the Bi p-electrons.