Correlated electrons in δ-plutonium within a dynamical mean-field picture

• Published in: Nature (London) Vol. 410; no. 6830; pp. 793 - 795
• Main Authors: Savrasov, S. Y, Kotliar, G, Abrahams, E
• Format: Journal Article
• Language: English
• Published: London Nature Publishing 12-04-2001; Nature Publishing Group
• Subjects: Actinides; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electron states; Electrons; Exact sciences and technology; Materials science; Methods of electronic structure calculations; Physics; Plutonium; Delta phase; Mean-field theory; Electron correlations; Total energy; Electronic structure; Theoretical study; Plutonium; Energy-level density
• ISSN: 0028-0836; 1476-4687
• DOI: 10.1038/35071035

Given the practical importance of metallic plutonium, there is considerable interest in understanding its fundamental properties. Plutonium undergoes a 25 per cent increase in volume when transformed from its α-phase (which is stable below 400 K) to the δ-phase (stable at around 600 K), an effect that is crucial for issues of long-term storage and disposal. It has long been suspected that this unique property is a consequence of the special location of plutonium in the periodic table, on the border between the light and heavy actinides-here, electron wave-particle duality (or itinerant versus localized behaviour) is important. This situation has resisted previous theoretical treatment. Here we report an electronic structure method, based on dynamical mean-field theory, that enables interpolation between the band-like and atomic-like behaviour of the electron. Our approach enables us to study the phase diagram of plutonium, by providing access to the energetics and one-electron spectra of strongly correlated systems. We explain the origin of the volume expansion between the α- and δ-phases, predict the existence of a strong quasiparticle peak near the Fermi level and give a new viewpoint on the physics of plutonium, in which the α- and δ-phases are on opposite sides of the interaction-driven localization-delocalization transition.