PbWO_4电子结构的密度泛函计算

ELECTRONIC STRUCTURES OF PbWO_4 CRYSTAL CALCULATED IN TERMS OF DENSITY FUNCTIONAL THEORY

采用基于密度泛函理论的相对论性离散变分和嵌入团簇方法模拟计算了PbWO4 晶体的本征能级结构 .发现价带主要由O2p轨道组成 ,含有部分W 5d轨道 ;导带主要由W 5d和O2 p的轨道组成 .发现导带底由Pb6 p1/ 2 的狭窄能级占有 .禁带宽度和价带宽度分别约为 4.8和 4eV .计算结果很好地解释了实验得到的反射谱 ,并从理论上分析了PbWO4

The electronic structure of PbWO\-4 crystal is studied with the relativistic self\|consistent discrete variational embedded cluster method in the framework of density functional theory. The results show that the valence band is mainly made up of O2p with a certain amount of W5d component, and the conduction band is mainly made up of the hybrid states of W5d and O2p. The bottom of the conduction band is first found to be occupied by a narrow Pb6p 1/2 state. The band gap and the width of valence band are around 4.8 and 4.0?eV, respectively. The results can successfully interpret the reflective spectrum of the crystal. The mechanism of the blue luminescence of the crystal is discussed.