高压下MgS的弹性性质、电子结构和光学性质的第一性原理研究

采用基于密度泛函理论(density functional theory)基础上的第一性原理赝势平面波方法, 计算研究了MgS晶体B2构型在不同压强下的几何结构、弹性性质、电子结构和光学性质. 计算结果表明, 在高压作用下, 该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. 同时, 对照态密度分布图及高压下能级的移动情况, 分析了MgS B2构型在高压作用下的光学性质, 发现高压作用下, 吸收光谱发生了明显的蓝移.

First principles study of the elastic, electronic and optical properties of MgS under pressure

The structural, elastic, electronic and optical properties of MgS B2 crystal under high pressure are studied by accurate first-principles plane wave pseudo-potential method which is based on the density functional theory. Our results show that the conduction band of the structure has a shift tendency toward higher energy, and the valence band has a shift tendency toward lower energy under high pressure. We analyze the optical properties associated with the partial density of states and the shift of energy level under high pressure. At the same time, the absorption spectrum of the MgS B2 crystal has an evident blue shift.