A DFT investigation on electronic structure, charge density, mechanical stability and thermodynamic properties of XAl3 (X =Sc, Yb and Lu) intermetallic compounds

Abstract The electronic structures of AuCu3-type XAl3 (X = Sc, Yb, Lu) compounds have been calculated using full potential linearized augmented plane wave (FP-LAPW) method within the density functional theory. The calculations have been performed using PBE-GGA, WC-GGA and PBE-sol GGA approximations. Electronic structures in these materials confirm metallicity. Our estimated ground state properties in case of ScAl3 are found in good agreement with the experimental values, while for YbAl3 and LuAl3 couldn’t be compared owing to non-existence of data. Charge density plots illustrate Sc/Yb/Lu–Al bonds are covalent, which signify according to Poisson ratio. For this reason, various elastic modulii, bulk to shear modulus ratios, Cauchy pressures were determined and it was found that XAl3 compounds show brittle nature. Finally, specific heat capacity, Debye temperature and Gruneisen parameter under pressure (0–15 GPa) and temperature (0–1000 K) are also elucidated using quasi harmonic model.