An ab-initio study of structural, electronic, and bonding properties of layer-structured ZnSb*

The orthorhombic structure of Zinc Antimonide (ZnSb) that belongs to the space group Pbca has been extensively studied because of its promising thermoelectric properties. It is of great interest to study the different phases of ZnSb in order to figure out the inherent possibilities of electronic properties. We performed ab initio total-energy calculations and geometry optimizations within Density Functional Theory (DFT) using the generalized gradient approximation (GGA) Perdew–Burke–Ernzerhof (PBE) functional and the projected augmented wave (PAW) method to investigate the structural, electronic, and bonding properties of tetragonal (P4/nmm) and wurzite (P63mc) phases of layer-structured ZnSb. We calculated the charge density, electron localization function (ELF), Bader charge analysis, density of states (DOS), and band Structures of these materials. The energy barrier between tetragonal and wurzite phases has been calculated using the climbing image Nudged Elastic Band (CI-NEB) method. The screened Heyd-Scuseria-Ernzerhof (HSE) hybrid functional within the PBE functional was also applied to improve the band gap and compared to the experiment.