Probing the 5f Electrons in Am-I by Hybrid Density Functional Theory

Abstract

The ground states of the actinides and their compounds continue to be matters of considerable controversies. Experimentally, Americium-I (Am-I) is a non-magnetic dhcp metal whereas theoretically an anti-ferromagnetic ground state is predicted. We show that hybrid density functional theory, which admixes a fraction of exact Hartree-Fock (HF) exchange with approximate DFT exchange, can correctly reproduce the ground state properties of Am. In particular, for a 0.40 fraction of HF exchange we obtain a non-magnetic ground state with equilibrium atomic volume, bulk modulus, 5f electron population, and the density of electronic states all in good agreement with experimental data. We argue that the exact HF exchange corrects the overestimation of the approximate DFT exchange interaction.

1 table, 4 figures. Chemical Physics Letters, in press (2009)

References in corpus (7)

• Nature of the 5f states in actinide metals
• Many-Body Electronic Structure of Americium metal
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• Does hybrid density functional theory predict a non-magnetic ground state for delta-Plutonium?
• Combining the Hybrid Functional Method with Dynamical Mean-Field Theory
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• The 5f localization/delocalization in square and hexagonal americium monolayers: A FP-LAPW electronic structure study

Cited by in corpus (1)

• Correlated 5f electronic states and phase stability in americium under high pressure: Insights from DFT+DMFT calculations