Site-Selective Electronic Correlation in alpha-Plutonium Metal
An understanding of the phase diagram of elemental plutonium (Pu) must include both the effects of the strong directional bonding and the high density of states of the Pu 5f electrons, as well as how that bonding weakens under the influence of strong electronic correlations. We present for the first time electronic-structure calculations of the full 16-atom per unit cell alpha-phase structure within the framework of density functional theory (DFT) together with dynamical mean-field theory (DMFT). Our calculations demonstrate that Pu atoms sitting on different sites within the alpha-Pu crystal structure have a strongly varying site dependence of the localization-delocalization correlation effects of their 5f electrons and a corresponding effect on the bonding and electronic properties of this complicated metal. In short, alpha-Pu has the capacity to simultaneously have multiple degrees of electron localization/delocalization of Pu 5f electrons within a pure single-element material.