statistical moment method;
elastic constant;
anharmonicity effects;
Cauchy relation;
tight-binding method;
density functional theory;
D O I:
10.1143/JPSJ.77.104801
中图分类号:
O4 [物理学];
学科分类号:
0702 ;
摘要:
The elastic properties of cubic metals have been studied using the analytic free energy formulas derived from the quantum statistical moment method (SMM). The three independent elastic constants C-11, C-12, and C-44 of cubic metals are calculated as a function of the temperature taking into account the anharmonicity of thermal lattice vibrations, and compared with the available experimental results. The particular attention has been paid to the understanding of the anharmonicity effects of thermal lattice vibrations on the elastic properties and thermodynamic crystalline stabilities of the metals in comparison with those by classical treatments of SMM.