Exploring Strongly Correlated Rare-Earth Intermetallics: Theoretical Insights into RIn3 and RSn3 (R = Sm, Eu, Gd)

Abstract

Abstract: The structural, electronic, magnetic, and elastic properties of Rin₃ and RSn₃ (R = Sm, Eu, Gd) were thoroughly investigated using the full potential linearized augmented plane wave plus local orbital (FP-LAPW+lo) method within the framework of density functional theory (DFT). Structural properties were evaluated using the local density approximation (LDA), generalized gradient approximation (GGA), and their band-correlated extensions, LDA+U and GGA+U. The computed lattice parameters exhibited excellent agreement with experimental results, and the divalent state of Eu was confirmed. To accurately predict the electronic properties, spin-orbit coupling (SOC) was incorporated, along with the splitting of the 4f states in rare-earth elements. Elastic properties, including bulk modulus, shear modulus, Young’s modulus, anisotropic ratio, Kleinman parameters, Poisson’s ratio, Lamé coefficients, sound velocities for shear and longitudinal waves, and Debye temperature, were calculated. Additionally, the Cauchy pressure and the B/G ratio were analyzed to determine the ductile or brittle nature of these compounds.