Comprehensive Analysis of Electronic Band Structure, Structural Phase Stability, and Optical Properties in AgMX2 Compounds

This study investigates the electronic structure, high-pressure phase transition, and optical properties of chalcopyrite compounds AgMX2 (M = Al, Ga, in; X = S, Se, Te) using the self-consistent Tight Binding Linear Muffin Tin Orbital Method (TB-LMTO) method. The equilibrium lattice constants in the body-centered tetragonal (BCT) phase were determined, and the energetic stability of the compounds was assessed by calculating total energies for both the BCT and high-pressure phases. The band structures were computed to analyze the metallic nature of the compounds under pressure. Additionally, optical properties such as the threshold frequency, static dielectric constants, refractive index, and degree of anisotropy were studied using the Full Potential Linear Muffin Tin Orbital Method (FP-LMTO) "LMTART" method. The results demonstrate the structural stability, band characteristics, and optical behavior of AgMX2 compounds, providing valuable insights into their potential applications.