Study of structural, elastic and electronic properties of GdX (X = Bi, Sb) compounds using LSDA and LSDA + U approach

In order to study the structural, and elastic properties of GdX (X = Bi, Sb), we employ all-electron full-potential linearized muffin-tin orbital method (FP-LMTO) within the frame of density functional theory (DFT). The exchange correlation energy is described in the local spin density approximation LSDA using the Perdew–Wang parameterization. The equilibrium lattice parameters, bulk modulus, transition pressure, elastic constants and their related parameters such as Poisson’s ratio, Young modulus, shear modulus and Debye temperature were calculated.We compared our obtained results with available experimental and theoretical data. They are in reasonable agreement. In this paper the electronic properties are treated with LSDA + U approach. Our results show that both compounds exhibit a semi metallic behavior.