An Ab Initio Investigation of CdSnN2 Under Uniaxial Compressions

Abstract

Herein, the behaviors of CdSnN2 are computationally investigated under uniaxial compressions based on density functional theory (DFT) calculations and a DFT‐1/2 scheme. When the compression is in [100] direction, phase transition is observed from Pna21 to Pnma phase when the compression is larger than 30 GPa, while no phase change is observed for uniaxial compressions along [010] and [001] directions. For the former one, the bandgap first increases with a maximum at 20 GPa, followed with a reduction upon the critical pressure and nearly a constant above 30 GPa. The bulk modulus nearly increases monotonically except for the transit region from 20 to 29 GPa, and the shear modulus decreases to 29 GPa and then increases for Pnma phase. When compression is along [010] direction, the bandgap nearly remains around 0.620 eV. The bulk modulus increases with a maximum around 25 GPa and then decreases, while the shear modulus monotonically decreases. The bandgap first increases and then shrinks monotonically with increasing compression in [001] direction. The bulk modulus monotonically increases and the shear modulus decreases. The absorption is then calculated and discussed. The anisotropic behaviors of CdSnN2 may hence indicate some potential applications.