Interpretation of the photoemission spectrum of chemisorbed carbon monoxide on Ni (100)

Cluster model calculations suggest that the molecular orbitals of CO are significantly perturbed upon chemisorption on Ni. The CO-Ni interaction is found to involve the Ni-d electrons in addition to the s-and p-derived states, contrary to some earlier suggestions. Based on our results, a new interpretation is proposed for the observed photoemission spectra of CO on Ni, which is consistent with the large bonding and relaxation shifts in other systems. © 1975.