A Density Functional Study of Atomic Carbon Adsorption on δ-Pu(111) Surface

Adsorption of atomic carbon on δ-Pu(111) surface is investigated systematically using density functional theory with RPBE functional. The adsorption energies, adsorption structures, Mulliken population, work functions, layer and projected density of states are calculated in wide ranges of coverage, which have never been studied before as far as we know. It is found that the hcp-hollow sites is the energetically favorable site for all the coverage range considered. The repulsive interaction is identified, and the adsorption energy decreases with the coverage, while work function increases linearly with the coverage. It is found that the C-Pu interaction is very strong due to the hybridization between the C 2p states and the Pu 5f, Pu 6p,Pu 6d states of topmost layer Plutonium atoms.