2009/08/12 by L. Petit, A. Svane, Z. Szotek +2 · 5 citations
Chemical Engineering · Chemistry · Materials Science · Physics and Astronomy · #Actinide #Atomic physics #Chemical physics #Chemistry #Computational chemistry #Density functional theory #Electron configuration #Electronic structure #Ground state #Inorganic chemistry #Ion #Ionic bonding #Ionic radius #Lanthanide #Metal #Molten salt chemistry and electrochemical processes #Nuclear Materials and Properties #Oxidation state #Oxide #Physics #Rare-earth and actinide compounds #Valency #cond-mat.mtrl-sci #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.81.045108
12 pages, 6 figures
arxiv created 2009/08/12 · openalex publication_date 2010/01/07 · arxiv updated 2015/05/13 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The ground-state electronic structures of the actinide oxides AO, A2O3, and AO2 (A=U, Np, Pu, Am, Cm, Bk, and Cf) are determined from first-principles calculations, using the self-interaction corrected local spin-density 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 A4+ ions in the dioxide and A3+ ions in the sesquioxides. In contrast, the A2+ ionic configuration is not favorable in the monoxides, which therefore become metallic. The energetics of the oxidation and reduction in the actinide dioxides is discussed, and it is found that the dioxide is the most stable oxide for the actinides from Np onward. 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.