First-principles calculations for elastic and electronic properties of ZnSnO3 under pressure

The LiNbO3 (LN)-type structure and the ilmenite (IL)-type structure of ZnSnO3 are investigated with the ultrasoft pseudopotential scheme in the frame of the local density approximation (LDA). The calculated lattice parameters of ZnSnO3 under zero pressure and zero temperature are in very good agreement with the existing experimental data. The pressure dependences of the elastic constants, Debye temperatures, Poisson's ratio, sound velocity, mechanical stability and mechanical anisotropy of the LN-type structure of ZnSnO3 have also been investigated. We find that the LN-type structure of ZnSnO3 is a mechanically stable phase under pressures up to 21 GPa; however, the mechanical anisotropy weakens with the increasing pressures. In addition, the calculated band structure indicates that LN-ZnSnO3 has a direct band gap of 1.669 eV, and the total and partial densities of states, under diverse pressures of the LN-type structure ZnSnO3 have also been obtained.