Structural, Electronic and Elastic Properties of ZnO and CdO: A First-Principles Study

Abstract A theoretical investigation of the structural, electronic and elastic properties of the transition metal monoxides Zinc monoxide (ZnO) and Cadmium monoxide (CdO) in the cubic B1 (rock-salt) B2 (CsCl) and B3 (zinc blende) phases are performed using the first-principles calculations. The optimized lattice parameters and their bulk modulus values are found to be in accord with the available experimental and other theoretical values. To understand the electronic properties of ZnO and CdO, their electronic band structures are analyzed. A pressure induced structural phase transition occurs from B3 to B1 at a pressure of 11.2 GPa and from B1 to B2 at even higher pressure of 243.3 GPa occurs in ZnO; whereas the transition is from B1 to B2 phase at a pressure of 88.5 GPa in CdO. The elastic constants are computed to investigate the mechanical stability at normal and elevated pressures. The pressure dependence of the various moduli, Poisson's ratio, anisotropy and the hardness of ZnO and CdO are also analyzed.