Electronic structure and thermodynamic properties of LiBC under high pressure

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/a_0 and c/c_0, the ratio c/a, the normalized primitive volume V/V_0 on pressure are given. The thermodynamic quantity (including the heat capacity C_V, Debye temperature \varTheta_\rm D, thermal expansion \alpha and Grüneisen parameter \gamma ) 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.