A first-principles study on the structural, thermal and electronic properties of cerium oxides by using different functionals

Abstract Cerium oxides, such as CeO 2 and Ce 2 O 3 , are of great scientific and technological importance for many potential applications. In this work, based on density functional theory (DFT), we performed systematic first-principles calculations to evaluate the performance of different exchange-correlation functionals, including the standard DFT (PBE, PBE sol ), Hubbard-corrected DFT (PBE, PBE sol )+ U , and HSE06 hybrid functionals, in describing the structural, thermal and electronic properties of cerium oxides. We calculated the equilibrium lattice parameters, thermal formation enthalpies, and electronic structures of CeO 2 and Ce 2 O 3 , with special attention paid to the gaps, positions and dispersions of O 2 p , Ce 4 f and Ce 5 d bands. Our results suggest that while HSE06 can describe the physical properties of CeO 2 with good accuracy with respect to experiment, PBE sol + U with a proper U value gives satisfactory results for Ce 2 O 3 . Our findings provide valuable information on using different functionals for describing the f -electron localization in cerium oxides, which may also be useful for further explorations of multi-functional materials and electronic devices based on strongly correlated oxide systems.