First Principle Calculations of Phases Stability and Electronic Structure of the Trihalide Perovskite RbSnBr3

The most commonly used and studied halide perovskite is ABX3, where A stands for Rb, B for Sn, and X for Br. A perovskite with high stability and ideal electronic band structure would be of essence, especially considering the materials used for solar cells. In this work, we have considered the two phases (cubic, orthorhombic) of RbSnBr3. the two structures are studied to understand how are the crystal structure stability, band gap and the electronic properties including the total density of states and the projected densities of state have been studied, we found a good agreement with experiments and other calculations. The material has a band gap of 0.57 ev resulting from the transition Br 4P5 → Sn 5P2 that makes the material as a good perovskite compound candidate of a great interest for potential solar-cell applications