Exploring Cu ₆ PS ₅ X argyrodites: A DFT study on structure, opto-electronic and thermal behavior

Structure, mechanical, elasto-acoustic and thermal properties are investigated using a systematic ab initio analysis within the density functional theory for Cu 6 PS 5 X (X[Formula: see text]Cl, Br, I) argyrodites. Both cubic compounds’ elastic characteristics are examined using the IRelast package, and the results demonstrate the mechanical stability of both compounds. The Debye and melting temperature of Cu 6 PS 5 Br are higher than Cu 6 PS 5 Cl and Cu 6 PS 5 I with low thermal expansion and expected higher lattice thermal conductivity. The electronic-band structure analyses depict a direct band gap of 2.06, 2.10 and 1.97[Formula: see text]eV, respectively. The optical characteristics of Cu 6 PS 5 X (X[Formula: see text]Cl, Br, I) are comprehensively examined. The compounds under study are potential candidates for optical applications. The optical properties reveal compounds’ utility for light absorption applications.