Correlation effect on electronic and lattice properties of cerium oxides: Insights from density functional theory to dynamical mean-field theory

In order to reveal static and dynamic correlation effect in Ce2O3 and CeO2 with an unified theoretical framework, we perform a first principles calculation on electronic and lattice properties of these two typical correlated systems using density functional theory (DFT) schemes as well as a many-body method merging DFT with dynamical mean field theory (DMFT), taking into account the spin-orbit coupling (SOC) interaction and on-site Coulomb repulsion between Ce 4f states. Results show that ground state of Ce2O3 is in the localized 4f1 atomic configuration, while CeO2 is a mixed-valence nf = 0.82 correlated system, which are in agreement with recent theoretical calculations and experimental observations. Lattice parameters, bulk modulus and band gap are also consistent with other theoretical calculations and experimental values. In order to compare with experimental angle-resolved photoemission spectrum (ARPES), momentum-resolved electronic spectrum function is also discussed.