采用基于第一性原理的密度泛函理论赝势平面波方法,对正交相OsSi2的电子结构、态密度和光学性质进行了理论计算,能带结构计算表明它是一种间接带隙半导体,禁带宽度为0·813eV;其价带主要由Os的5d和Si的3p态电子构成;导带主要由Si的3s,3p以及Os的5d态电子构成;静态介电常数ε1(0)=15·43;折射率n=3·93·并利用计算的能带结构和态密度分析了OsSi2的介电函数、吸收系数、折射率、反射率、光电导率和能量损失函数的计算结果,为OsSi2的设计与应用提供了理论依据.
Electronic structure, densities of states and optical properties of orthorhombic OsSi2 was calculated by the first-principle density function theory pseudopotential method. The calcul ated results show that OsSi2 is an indirect semiconductor with the band gap of 0.813 eV, the valence bands of OsSi2 are mainly composed of Os 5d and Si 3p, the conduction bands are mainly composed of Si 3p, 3s as well as Os 5d . The stastic dielectric function ε-1(0) is 15.43, the reflectivity n-0 is 3.93. Furthermore, the dielectric functions, refractivity index, reflectivity, absorption, conductivity and loss function of OsSi2 are analyzed in terms of the calculated band structure and densities of states. The results offer theoretical data for the design and application of OsSi2.