A periodical density functional theory study of CO adsorption on δ-Pu(111) surface

CO adsorption on δ-Pu(111)surfaces using the generalized gradient approximation of the density functional theory with PW91 functionals has been studied.For the δ-Pu(111)surface,the O-down adsorption is less stable than the C-down adsorption which is found to be a strong chemisorption.The center position of δ-Pu(111)surface is the preferred adsorption site with chemisorption energy of-1.236 eV and distance of 0.212 2 nm and C—O bond length of 0.120 8 nm.The coordination numbers play a significant role in the chemical bonding process.Mulliken charge distribution analysis indicates that the interaction of Pu with CO mainly takes place in the first layer and that the other two layers are only slightly affected.The adsorption of CO adsorptiom on δ-Pu surfaces make the surface work functions of Pu metal distinctly increased.