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

• The bulk moduli of zinc-blende ZnO have been investigated using first-principles calculation.
• Particular attention is paid to the predictions of the BT, BT′, and BT′′ of zinc-blende ZnO.
• The quasi-harmonic Debye model is applied to take into account the thermal effect.

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.