First principles investigation of the structural, thermophysical, electronic and optical properties of cubic perovskite BaPdO3

In this work, cubic perovskite BaPdO 3 has been investigated using density functional theory (DFT) calculations to speculate its elastic, thermal, electronic and optical properties for the first time. The negative formation energy of BaPdO 3 confirms its thermodynamic stability. A detailed analysis of the calculated elastic constants and moduli reveals that BaPdO 3 is mechanically stable, ductile, machinable, moderately hard and elastically anisotropic. The Debye and melting temperatures of BaPdO 3 have been predicted from the elastic constants. Analysis of electronic charge density and Mulliken bond population indicates mixed ionic-covalent bonding characteristics, with ionic interactions playing the dominant role. The calculated electronic band structure, both with and without spin-orbit coupling (SOC), together with the density of states, confirms the metallic nature of BaPdO 3 . The Fermi surface consists of both electron-like and hole-like sheets. The electrical conductivity curve indicates a high level of conductivity. At finite temperature, anharmonic effects stabilize the phonons that are imaginary at 0 K, leading to a stable phase. The calculated optical parameters are consistent with the features of the band structure and density of states. BaPdO 3 exhibits high reflectivity in the visible light range, strong absorption in the ultraviolet region and a high refractive index at low photon energies. These electronic and optical properties suggest that BaPdO 3 may be promising for applications in which metallic behavior is advantageous, such as electrodes and reflective coatings.