A Computational Investigation for Physical Property and Superconductive Nature of CaRh2Si2 And SrCo2Si2 by DFT Simulation

This research focuses on the mechanical, electronic, optical, and superconductive nature of CaRh₂Si₂ and SrCo₂Si₂, which have structures similar to those of the ThCr₂Si₂ compound. The investigation used a first-principles approach based on DFT, with calculations performed via CASTEP. The optimized lattice parameters closely match previously synthesized parameters. These materials possess positive elastic constants, which ensure they are mechanically stable. Additionally, Pugh’s and Poisson’s ratio values suggest that CaRh₂Si₂ and SrCo₂Si₂ exhibit brittle behavior. At the Fermi level, the valence and conduction bands overlap, indicating the metallic characteristics of both compounds. Various optical properties were investigated, with the reflectance parameter demonstrating that CaRh₂Si₂ and SrCo₂Si₂ have the potential to be effective solar reflectors. The photoconductive nature and absorption parameters begin when the photon’s energy is zero, confirming these material’s metallic characteristics. The thermodynamic properties of CaRh₂Si₂ and SrCo₂Si₂ were derived from their elastic stiffness constants, and the Debye temperatures of these two compounds are 576.08 K and 446 K, respectively, based on the elastic constants data. In BCS (Bardeen-Cooper-Schrieffer) theory, superconductivity occurs when electrons form Cooper pairs at low temperatures due to attractive forces mediated by phonons. The superconducting properties suggest that CaRh₂Si₂ and SrCo₂Si₂ moderately coupled superconductors. The outcomes of this study could serve as an adequate basis for further investigations.