The structural, elastic and thermodynamical properties of zinc-blende BeTe from first-principles

The structural, elastic and thermodynamic properties of BeTe with cubic zinc-blende (ZB) structure are investigated by performing first-principles calculations within generalized gradient approximation (GGA). The calculated results are in excellent agreement with the available experimental data and other theoretical results. It is found that the ZB structure BeTe is unstable above 40 GPa. The thermodynamic properties of the ZB structure BeTe are calculated by using the quasi-harmonic Debye model. The pressure–volume–temperature (P–V–T) relationship, the variations of the thermal expansion coefficient α and the heat capacity CV with pressure P and temperature T, as well as the Grüneisen parameter–pressure–temperature ( γ –P–T) relationship are obtained in the range of the pressure 0–45 GPa and the temperature 0–1200 K.