Evidence of Coulomb correction and spin-orbit coupling in rare-earth dioxides CeO2, PrO2 and TbO2: An ab initio study

Abstract

The current study investigates the structural, elastic, electronic and optical properties of CeO 2, PrO 2 and TbO 2 using the full potential (linearized) augmented plane wave plus local orbital method within the WuCohen generalized gradient approximation (GGA) with Hubbard (U) correction and spinorbit coupling (SOC). The GGAU implementation lead us to describe correctly the relativistic effect on 4f electrons for CeO 2. We clarify that the inclusion of the Hubbard U parameter and the spinorbit coupling are responsible for the ferromagnetic insulating of PrO 2 and TbO 2. The magnetic description is achieved by the spin-density contours and magnetic moment calculations, where we show the polarization of oxygen atoms from the rare earth atoms. The mechanical stability is shown via the elastic constants calculations. The optical properties, namely the dielectric function and the reflectivity are calculated for radiation up to 12 eV, giving interesting optoelectronic properties to these dioxides