Eur. Phys. J. B 78, 13-22 (2010)
https://doi.org/10.1140/epjb/e2010-10299-1

A hybrid DFT description of the (0001) surface of americium-I

Physics Department, University of Texas at Arlington, Arlington, 76019 Texas, USA

Corresponding author: ^a akr@uta.edu

Received: 12 April 2010
Revised: 9 September 2010
Published online: 12 October 2010

Abstract

Using a periodic slab model for the (0001) surface of americium-I (Am-I) and the full-potential linear augmented plane wave (FP-LAPW) plus local basis implementation of hybrid density functional theory (HYB-DFT), we show that with a fraction of 0.40 Hartree-Fock (HF) exchange, the non-magnetic nature of the Am-I surface is well described and the electronic properties are in good agreement with recent photoemission spectroscopy data. The work function and surface energy of the non-magnetic semi-infinite surface are predicted to 3.46 eV and 1.03 J/m², respectively. As a function of slab thickness, the surface properties, namely the surface energy, work function, and slab incremental energy converge after five layers. A five layer slab is thus deemed to be sufficient to very accurately model the adsorption of impurities on the surface and adsorbate-induced changes in the work function. A layer-by-layer examination of the nine-layer non-magnetic slab clearly indicates that the 5f electrons are uniformly localized, that is, the 5f electron localization is independent of the position of the layer.