Electronic structure and ionicity of actinide oxides from first principles calculations

Abstract

The ground state electronic structures of the actinide oxides AO, A2O3 and AO2 (A=U, Np, Pu, Am, Cm, Bk, Cf) are determined from first-principles calculations, using the self-interaction corrected local spin-density (SIC-LSD) approximation. Emphasis is put on the degree of f-electron localization, which for AO2 and A2O3 is found to follow the stoichiometry, namely corresponding to A(4+) ions in the dioxide and A(3+) ions in the sesquioxides. In contrast, the A(2+) ionic configuration is not favorable in the monoxides, which therefore become metallic. The energetics of the oxidation and reduction of the actinide dioxides is discussed, and it is found that the dioxide is the most stable oxide for the actinides from Np onwards. Our study reveals a strong link between preferred oxidation number and degree of localization which is confirmed by comparing to the ground state configurations of the corresponding lanthanide oxides. The ionic nature of the actinide oxides emerges from the fact that only those compounds will form where the calculated ground state valency agrees with the nominal valency expected from a simple charge counting.

12 pages, 6 figures

References in corpus (4)

• Nature of the 5f states in actinide metals
• Mott Transition of MnO under Pressure: Comparison of Correlated Band Theories
• Self-interaction Corrected Local Spin Density Theory of 5f Electron Localization in Actindes
• X-ray absorption branching ratio in actinides: LDA+DMFT approach

Cited by in corpus (23)

• Resolution-of-identity approach to Hartree-Fock, hybrid density functionals, RPA, MP2, and \textit{GW} with numeric atom-centered orbital basis functions
• Ground state properties and high pressure behavior of plutonium dioxide: Systematic density functional calculations
• Phonon spectrum, thermal expansion and heat capacity of UO${}_2$ from first-principles
• Phonon spectrum, thermodynamic properties, and pressure-temperature phase diagram of uranium dioxide
• Thermodynamic properties and structural stability of thorium dioxide
• Optical properties of UO2 and PuO2
• A Self-consistent DFT+DMFT scheme in the Projector Augmented Wave : Applications to Cerium, Ce2O3 and Pu2O3 with the Hubbard I solver and comparison to DFT+U
• Rare Earth Monopnictides and Monochalcogenides from First Principles: Towards an Electronic Phase Diagram of Strongly Correlated Materials
• Crystal field and magnetic structure of UO${}_2$
• Electronic structure and core-level spectra of light actinide dioxides in the dynamical mean-field theory
• First-principles study of surface properties of PuO2: Effects of thickness and O-vacancy on surface stability and chemical activity
• First-principles study on oxidation effects in uranium oxides and high-pressure high-temperature behavior of point defects in uranium dioxide
• Towards a first-principles determination of effective Coulomb interactions in correlated electron materials: Role of intershell interactions
• Capturing the ground state of uranium dioxide from first principles: crystal distortion, magnetic structure, and phonons
• The different roles of Pu-oxide overlayers in the hydrogenation of Pu-metal: An ab initio molecular dynamics study based on vdW-DFT+U
• Crystal dynamics and thermal properties of neptunium dioxide
• Self-consistent density functional calculations of the crystal field levels in lanthanide and actinide dioxides
• The environmental dependence of redox energetics of PuO2 and α-Pu2O3: A quantitative solution from DFT+U calculations
• Ideal strengths and bonding properties of PuO2 under tension
• Electron correlation and spin-orbit coupling effects in US3 and USe3
• Reexaming the ground state and magnetic properties of curium dioxide
• Theoretical assessment on the possibility of constraining point defect energetics by pseudo-phase transition pressures
• Theory of valence-band and core-level photoemission from plutonium dioxide