【摘要】 运用基于密度泛函理论的平面波赝势方法(PWP),计算研究了氧化镉NaCl结构(B1结构)和CsCl结构(B2结构)在不同压力条件下的几何结构、弹性性质、电子结构和光学性质。交换关联能分别采用广义梯度近似(GGA)和局域密度近似(LDA)。通过比较计算和实验得到的晶格常数和体模量不难发现,LDA的计算结果更符合实验值。在高压的作用下,两种结构的导带能级有向高能级移动的趋势,而价带能级有向低能级移动的趋势,因此直接带隙变大。同时,对照态密度分布图及高压下能级的移动情况,分析了CdO两种结构在高压作用下的光学性质。更多还原

【Abstract】 The structural,elastic,electronic and optical properties of CdO under high pressure were studied by plane wave pseudo-potential method which based on the density functional theory.The generalized gradient approximation and local density approximation were used to describe the exchange-correlation potential.Comparing the lattice constants and bulk modules between experimental and computational,we can find the calculated results by local density approximation are well agreement with the experimental values.Under high pressure,the conduction bands of two structures have a shift tendency to higher energy,and the valence bands have a shift tendency to lower energy.We analyze the optical properties about the two structures associate with the partial density of states and the shifting of energy levels under high pressure.更多还原