Modeling of structural, elastic, mechanical, acoustical, electronic and thermodynamic properties of XPdF3 (X = Rb, Tl) perovskites through density functional theory

Abstract

The present article reports a comprehensive study on structural, elastic, mechanical, acoustical, electronic and thermodynamic properties of XPdF3 (X = Rb, Tl). This study has been carried out using Wien2k computational code written in Fortran language and based on density functional theory. The obtained results explored the ground state stability of these compounds in non magnetic phase. The calculated structural properties including lattice constant, bulk modulus, ground state energy, energy of formation were compared with available literature. In addition, from elastic constants, bulk, shear and elastic moduli, Poisson’s ratios and anisotropy factors were calculated. Furthermore, from criteria of Pugh’s ratio and Cauchy pressure, the materials were found as ductile. The sound velocities in TlPdF3 were examined as lower than RbPdF3 because of comparatively heavier mass of Tl than Rb atom. The obtained electronic properties give the indications of inclusion of these compounds in category of metallic perovskites. Moreover, the thermodynamic parameters like thermal expansion, heat capacity, Debye temperature and Grüneisen parameter were computed using Debye model.