Molecular orbital approach to the CO chemisorption on Cu(100)

A charge self-consistent molecular orbital calculation is performed to examine the chemisorption properties of CO on Cu(100) surface. It is found that 1-, 2- and 4-fold sites are all possible and Co is perpendicular to the substrate with carbon bonds to the surface copper atoms. Fourfold indentation is predicted as the most stable site. Size effect plays a reasonable role in determining adsorption geometry. Preliminary discussions have been made to elucidate the origin of two CO chemisorption phases. (author). 16 refs, 4 figs, 2 tabs