Phase transition and thermodynamic properties of MgTe under high pressure

Abstract

The transition phase of MgTe from rock salt structure (B1) to cesium chloride structure (B2) is investigated by ab initio plane-wave pseudopotential density functional theory method. The thermodynamic properties of the B1 and B2 structures are obtained through the quasi-harmonic Debye model. Our results indicated that MgTe undergoes a structural phase transition from B1 to B2 at about 90.32 GPa. The dependences of the relative volume V/ V 0 on the pressure P, the Debye temperature Θ and heat capacity C V on the pressure P, the Grüneisen parameter ratio ( γ − γ 0)/ γ 0 on pressure P, the bulk moduli ratio ( B − B 0)/ B 0 on pressure P, as well as the heat capacity C V on the temperature T are estimated.