Atomic position dependent structural, electronic, mechanical and optical properties of ZnSbF3 fluoroperovskites

In this study, we have investigated the structural, electronic, mechanical, and optical properties of ZnSbF3-I and ZnSbF3-II by altering the position of Zn and Sb through density functional theory (DFT) for the first time. The structural stability of both structures was confirmed by calculating formation enthalpy. A remarkable phenomenon has been observed from the electronic band structures analysis, whenever altering the atomic of Zn and Sb, which leads to a transition from semiconducting, ZnSbF3-I to metallic, ZnSbF3-II conductivity. The obtained bandgap value of ZnSbF3-I is of the order of 0.97 eV with indirect transition and the spin-orbit coupling (SOC) effect reduced the band gap energy to 0.49 eV. Density of states (DOS) curves revealed that the Sb-5p state is mainly responsible for this phase transition. The estimated elastic constants suggested that both phases are mechanically stable. By assessing the different elastic parameters, it can be concluded that both phases are mechanically ductile, machinable, isotropic, and soft in nature. A large value of bulk modulus for ZnSbF3-II indicates that it is harder and cannot be compressed as easily as ZnSbF3-I. The structures exhibit high efficiency in absorbing UV light. ZnSbF3-II's strong reflectivity in the infrared spectrum makes it an option to use for IR shielding. This study will guide further theoretical and experimental investigation.