Theoretical study of the structural, electronic structure, fermi surface, electronic charge density and optical properties of the of LnVO4 (Ln= Sm, Eu, Gd and Dy)

Abstract

We present first-principles calculations of the electronic structure, Fermi surface, electronic charge density and optical properties of LnVO4(Ln= Sm, Eu, Gd and Dy) based on density-functional theory using the local density approximation (LDA), generalized-gradient approximation (GGA) and the Engel Vosko GGA formalism (EV-GGA). The calculated band structure and density of states show that LnVO4 compound is metallic. The total DOS at Fermi level N(EF) were 1.49, 0.95, 1.93 and 4.69 states/eV unit cell, and the bare electronic specific heat coefficient (γ) are 0.26, 0.16, 0.33 and 0.81 mJ/mol-K2 for SmVO4, EuVO4, GdVO4 and DyVO4, respectively. The Fermi surface of EuVO4 compound is composed of one band and SmVO4, GdVO4 and DyVO4 composed of two bands crossing along the γ-A direction of Brillion zone. The bonding features are analyzed by using the electronic charge density contour in the (1 0 1) crystallographic plane. We found that Ln-O and V-O atoms forms a strong covalent. For further insight information about the electronic structure, the optical properties are derived and analyzed.