Pressure effects on structural, elastic and electronic properties of BaZnO2: first-principles study

The structural, elastic and electronic properties of BaZnO2 under pressure are investigated by the plane wave pseudopotential density functional theory (DFT). The calculated lattice parameters and unit cell volume of BaZnO2 at the ground state are in good agreement with the available experimental data and other theoretical data. The pressure dependences of elastic constants C-ij, bulk modulus B, shear modulus G, B/G, Poisson' s ratio sigma, Debye temperature Theta and aggregate acoustic velocities V-P and V-S are systematically investigated. It is shown that BaZnO2 maintains ductile properties under the applied pressures. Analysis for the calculated elastic constants has been made to reveal the mechanical stability and mechanical anisotropy of BaZnO2. At the ground state, the calculated compressional and shear wave velocities are 8.26km/s and 1.81km/s, respectively, and the Debye temperature Theta is 240.8K. The pressure dependences of the density of states and the bonding property of BaZnO2 are also investigated.