Electronic structure and thermodynamic properties of LiBC under high pressure

• 来源期刊: 中国物理B（英文版）
• 关键词: thermodynamic properties electronic structure density functional theory LiBC
• 年，卷（期）: 2008,（7）
• 页码范围: 2639-2645
• 页数: 7页
• 语种: 英文

摘要

This paper investigates the electronic structure and thermodynamic properties of LiBC in the hexagonal structure by using the generalized gradient approximation (GGA) and local density approximation correction scheme in the frame of density functional theory. The geometric structure of LiBC under zero pressure, and the dependences of the normalized lattice parameters a/a0 and c/c0, the ratio c/a, the normalized primitive volume V/V0 on pressure are given. The thermodynamic quantity (including the heat capacity CV, Debye temperature θD, thermal expansion α and Gruneisen parameter γ) dependences on temperature and pressure are obtained through the GGA method and the quasi-harmonic Debye model. The band structures and density of state of LiBC under different pressures have also been analysed.