(1. 中南大学 物理科学与技术学院,长沙 410083;
2. 湘南学院 物理系,郴州 423000;
3. 中南大学 材料科学与工程学院,长沙 410083)
摘 要: 采用第一性原理赝势平面波方法对闪锌矿结构AlN、AlP和AlAs的电子结构,介电和弹性性质进行计算,结果表明:基于密度函数扰动理论计算的这些材料的介电和弹性性质与其它第一性原理和分子动力学计算值一致性较好,但与实验值之间有一定的差异;晶格参数的优化、赝势的选取和交换关联项的选择都对计算结果有较大影响。根据计算的弹性常数绘制了这些材料特征平面(101)面的弹性模量图,为这方面材料的力学研究提供参考。
关键字: 电子结构;玻恩有效电荷;介电张量;弹性常数
(1. School of Physics Science and Technology, Central South University, Changsha 410083, China;
2. Department of Physics, Xiangnan University, Chenzhou 423000, China;
3. School of Material Science and Engineering, Central South University, Changsha 410083, China)
Abstract:With the pseudopotential plane-wave method of first principle, the electronic structure, dielectric and elastic properties of zinc-blende AlN, AlP and AlAs were studied. The results show that based on the density functional perturbation theory, the calculated results are in good agreement with other ab initio and molecular dynamics calculated values, but have definite difference with the experimental data. The calculated values are affected by lattice constant, selection of pseudopotential and selection of exchange-correlation energy. Based on the calculated elastic constant, the elastic moduli of characteristic plane (101) are figured, which offers reference to mechanical study of these materials afterward.
Key words: electronic structure; Born effective charge; dielectric tensor; elastic constant