Density functional theory analysis of the structural, electronic, elastic, phonon dispersion and AIMD properties of KMgX (X = O, S, Se).

Perovskite chalcogenides have attracted significant interest due to their potential applications in optoelectronics, catalysis, and renewable energy systems. This paper examines the structural, electronic, elastic, and phononic properties of KMgX (X = O, S, Se) using density functional theory (DFT) in the context of the full-potential linearized augmented plane wave plus local orbital (FP-LAPW + lo) approach. Their stability in the cubic phase (3̄ symmetry) is confirmed by the computed lattice parameters for KMgO (4.