Orientation of CO on Pt(111) and Ni(111) Surfaces from Angle-Resolved Photoemission

Abstract
Angle-resolved photoemission spectra of the molecular obritals of chemisorbed CO on Pt(111) and Ni(111) substrates show a strong angular variation of the peak intensity ratio. Comparison with Davenport's Xα calculations establishes that CO stands up on these substrates, with the carbon atom bonded to the substrate. The Pt 5d(t2g) orbitals are found to be strongly involved in chemisorption bonding to CO.