A first principle study of pressure-induced effects on phase transitions, band structures and elasticity of zinc oxide

Using the first-principles projector-augmented wave (PAW) method, the pressure induced effects on solid–solid phase transition, electronic band structures and elasticity of zinc oxide are investigated. The four possible structures are considered here, including rocksalt (B1), CsCl (B2), zinc blende (B3), and wurtzite (B4). It is found that structural properties and phase transition points by the PBEsol method are better than those computed using the standard local density approximation and Perdew, Burke and Ernzerhof functionals. Moreover, using the hybrid HSE06 functional, the band structures around phase transition points are displayed. The predicted fundamental gaps of the four considered structures provide improvements over directly density functional theory calculations. Meanwhile, the effective masses for the electrons in the conduction band and the holes in the valence band are derived. Furthermore, the elastic abnormal behavior is achieved around the phase transition points. For B4, B1 and B2 structures, the longitudinal and transverse sound velocities are evaluated along significant symmetry directions with pressure, and it still awaits experimental confirmation.