A study of the electronic properties of ErB2 compound by using the PBE approximation and PBE0 hybrid functional

We report calculations from first principles to determine the structural and electronic properties of ErB 2 compound using the Density Func- tional Theory (DFT) and the Full-Potential Linearized Augmented Plane Waves (FP-LAPW) method. For the description of the electron- electron interaction, the Generalized Gradient Approximation Perdew-Burke-Ernzerhof (GGA-PBE) and PBE0 Hybrid Functional were employed. From the density of states (DOS), it is found that the addition of a fraction of the exact Hartree-Fock exchange energy, in the PBE approximation, evidence the localization of the 4f -Er orbitals, which favors electronic spin polarization of these orbitals in the ErB 2 compound. The PBE0 scheme is justified because it best describes the electronic and magnetic properties of strongly correlated systems than the PBE approximation.