1. Department of Physics and Astronomy and Center for Materials Theory, Rutgers University, Piscataway, New Jersey 08854-8019, USA

Correspondence to: S. Y. Savrasov Correspondence and requests for materials should be addressed to S.Y.S. (e-mail: Email: savrasov@physics.rutgers.edu).

Abstract

Given the practical importance of metallic plutonium, there is considerable interest^{1, 2, 3} in understanding its fundamental properties. Plutonium undergoes a 25 per cent increase in volume⁴ when transformed from its -phase (which is stable below 400 K) to the -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 important⁵. 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 - and -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 - and -phases are on opposite sides of the interaction-driven localization–delocalization transition.

1. Department of Physics and Astronomy and Center for Materials Theory, Rutgers University, Piscataway, New Jersey 08854-8019, USA

Correspondence to: S. Y. Savrasov Correspondence and requests for materials should be addressed to S.Y.S. (e-mail: Email: savrasov@physics.rutgers.edu).