Bonding and electronic structure of coadsorbed CO and K on Ru(001)

Abstract
The influence of coadsorbed potassium on the electronic structure of CO on Ru(001) was studied by the combined use of x-ray and polarized uv photoemission, as well as high-resolution Auger spectroscopy. The results from dense adlayers indicate that the strong electronic interaction of CO with neighboring K atoms occurs via the substrate leading to a rehybridization of the Ru-C-O bond of the perpendicularly adsorbed CO molecule and thus to some changes in the valence-band structure. The coverage-dependent binding-energy shifts are explained on the basis of a recent reinterpretation of the CO-Me bond.