First-principles investigation of temperature dependent thermal properties of ternary MgCu 2 O 3 using quasi-harmonic approximation

Abstract The thermal properties of ternary MgCu 2 O 3 compound have been investigated using density functional theory (DFT) in conjunction with density functional perturbation theory (DFPT) and quasi-harmonic approximation (QHA). The phonon band structure and phonon density of states (PhDOS) are calculated to establish the lattice dynamical stability and vibrational characteristics of the compound. Based on the phonon spectra, the temperature-dependent thermodynamic quantities, including the thermal expansion coefficient, heat capacities at constant pressure and constant volume, entropy, and isothermal bulk modulus, are evaluated. The results provide comprehensive insight into the vibrational and thermodynamic behaviour of MgCu 2 O 3 , highlighting the crucial role of lattice dynamics in governing its thermal properties.