单斜BiScO3和BiCrO3的电子结构和光学性质的第一性原理比较研究
A comparative first-principles study of electronic structure and optical properties of monoclinic BiScO3 and BiCrO3

采用基于密度泛函理论的第一性原理赝势平面波方法，对单斜BiScO3和BiCrO3的电子结构和光学性质进行了比较研究。结果表明：BiScO3为磁绝缘体，带隙为直接带隙，BiCrO3为间接带隙磁性半导体；BiScO3和BiCrO3都不吸收能量小于1.02 eV的光子，BiScO3吸收可见光的能力强于BiCrO3。
The energy bands，densities of states and optical properties of BiScO3 and BiCrO3 are investigated by using the plane wave ultrasoft pseudopotential method based on the first-principles density functional theory. The calculated energy bands indicate that BiScO3 is an insulator with a direct band gap and nonmagnetic property, whereas BiCrO3 is a magnetic semiconductor with an indirect band gap. The valence energy band in BiScO3 (or BiCrO3) is dominated by O-2p and Sc-3d (or Cr-3d) levels. In addition，the calculations of optical properties for BiScO3 and BiCrO3 crystals show that both crystals do not absorb photons less than 1.02 eV in energy. The visible light absorbing ability of BiCrO3 is stronger than that of BiScO3.