Metallic and optoelectronic properties of Rb ₂ AgSnX ₆ (X=Cl, Br, I) double perovskites for photonic and transparent conductor applications: A DFT study

Double halide perovskites have obtained significant interest due to their adaptable structural and electronic properties, positioning them as promising candidates for next-generation optoelectronic devices. This study investigates the structure and electronic properties of Rb 2 AgSnX 6 (where [Formula: see text], Br, I) double halide perovskites using density functional theory (DFT). The analysis reveals that these structures exhibit metallic properties, indicating their suitability for various applications. Furthermore, the structural analysis demonstrates that these compounds are stable, characterized by strong lattice dynamics and minimal energy requirements for their formation. The optical properties of the double perovskites are examined using density functional perturbation theory (DFPT). Our results suggest that these perovskite structures exhibit limited interaction with electromagnetic radiation at higher photon energies while showing significant responsiveness at lower photon energy levels. In addition, we employed ab initio molecular dynamics (AIMD) simulations to determine how stable the Rb 2 AgSnX 6 ([Formula: see text], Cl, I) structures are at different temperatures. The results confirm that all compounds maintain structural integrity throughout the simulation, reinforcing their dynamic stability. The obtained results highlight the viability of Rb 2 AgSnX 6 as an environmentally friendly alternative to Pb-based perovskites, providing invaluable information for the future design and optimization of energy and electronic devices.