Size effects on the electronic and magnetic properties of PuO2 (111) surface

Detailed studies of the PuO2 (111) surface, up to 6 molecular layers, are presented using all-electron hybrid density functional theory. The periodic slabs models for surfaces are studied to probe the effects of slab size on predicted surface properties. Ferromagnetic (FM) and anti-ferromagnetic (AFM) configurations are considered with and without spin orbit coupling. The surface energies of the slabs are found to be in 0.7-0.8 J/m(2) range whereas the average work function ranges from 5.2 to 5.3 eV. The band gap and pDOS plots show PuO2 surfaces in general retain the bulk's Mott insulator property; however the slabs are oxygen terminated, as a result the outermost PuO2 layer shows charge-transfer type of insulating behavior. (C) 2015 Elsevier B.V. All rights reserved.