Screening the Structural, Tuning Band Gaps, Optical and Thermal Properties of Inorganic A2AgRhF6 (A = Na, Rb) Double Perovskites Halide Using DFT Calculations

A comprehensive analysis of halide double perovskites A₂AgRhF₆ (A = Na, Rb) compounds are performed under the DFT framework. The optimization curve, negative value of the formation energy, and tolerance factor of both A₂AgRhF₆ (A = Na, Rb) materials reveal stability. In electronic features including band dispersions and the density of states revealed the semiconductor response of both perovskites with an indirect bandgap. The bandgap values for Na₂AgRhF₆ are 2.59 eV and 2.71 eV for Rb₂AgRhF₆ respectively. The computed optical attributes display outstanding properties having highest absorption coefficient in visible and UV region, minimum loss function and low reflectivity. Additionally, thermoelectric response of both double perovskites is very impressive due to the high electrical conductivity, moderate thermal conductivity, accumulating the highest ZT_e values of 0.73 and 0.72 for Na₂AgRhF₆ and Rb₂AgRhF₆. The estimated results of F-based double halide perovskites nominate the potential applications in the optoelectronics and thermoelectric industry.