Orthorhombic structure and optoelectronic properties of 3d transition metal diantimonides TMSb2 (TM2+ = V, Cr, Fe)

Abstract

Inorganic transition-metal materials have attracted widespread attention in the field of opto-spintronics technology due to their unique optical and electronic structures. Tuning the physical properties of diantimonide materials by introducing 3d transition-metal (TM) elements is an effective means to obtain functional compounds to be applicable in the field of optoelectronics devices. In this regard, based on ab-initio calculations, we have investigated the structural, electronic and optical properties of diantimonides TMSb₂ (TM = V, Cr, Fe) according to the density functional theory (DFT) executed in Wien2k package. The Perdew-Burke-Ernzerhof (PBE) functional under generalized gradient approximation (GGA) and (GGA + U) are adopted to carry out the exchange correlation calculations. Our DFT results demonstrate that TMSb₂ crystalize in marcasite structure with orthorhombic symmetry (S.G.: Pnnm, #58, Z = 2). Utilizing the PBE-GGA and PBE-GGA + U methods, we calculated the band structure, as well as the total density of states and partial density of states, which confirm that the TMSb₂ materials exhibit ferromagnetic metallic behavior. In addition, the optical properties are investigated as a function of photon energy and we found that TMSb₂ show favourable absorption, conductivity, refractivity, and reflectivity. The high optoelectronic responses at the low energies make TMSb₂ promising materials for optoelectronics applications.