Plutonium: The Density-Functional-Theory Point of View

摘要

Density-functional theory (DFT) is a remarkably successful tool for describing many metals throughout the Periodic Table. Here we present the results of this theory when applied to plutonium metal, the perhaps most complex and difficult-to-model metal of all. The fundamental product of DFT is the ground-state total energy. In the case of Pu, we show that DFT produces total energies that can predict the complex phase diagram accurately. Focusing on the O phase, we show that DFT electronic structure is consistent with measured photoemission spectra. The observed non-magnetic state of O-Pu could possibly be explained in DFT by spin moments, likely disordered, that are magnetically neutralized by anti-parallel aligned orbital moments. As an alternative to this non-magnetic model an extension of DFT with enhanced orbital polarization is presented in which magnetism can be suppressed.