Prediction of the pressure–volume–temperature equation of state for zinc-blende ZnO from quasi-harmonic Debye model

The pressure–volume–temperature relationship and bulk modulus of ZnO with zinc-blende phase are investigated by means of first-principles density functional theory calculations combined with the quasi-harmonic Debye model in which the phononic effects are considered. Particular attention is paid to the predictions of the first and second pressure derivatives of isothermal bulk modulus which play central role in the formulation of approximate equations of state for the first time. The properties of ZnO with zinc-blende phase are summarized in the pressure range of 0–7.45 GPa and the temperature up to 2000 K.