THEORETICAL INVESTIGATION OF ETHYLENE ADSORBED ON NI(100) SURFACE BY THE MULTIPLE-SCATTERING CLUSTER METHOD

In this paper the carbon K-edge near edge X-ray absorption fine structure spectra (NEXAFS) of adsorption system C2H4/Ni(100) are calculated using the multiple-scattering cluster method. By a comparison between the theoretical results and experimental spectra, the chemisorption geometry of this system has been determined. The result shows that the molecule is adsorbed on the perpendicular bridge site, and the distance between the C atom and the nearest Ni atom is 1.70 angstrom, while the molecular plane tilting to the surface is 50-degrees. It is found that the interaction between hydrogen atom and Ni substrate plays an important role in the formation of the adsorption structure. The above results are supported by other evidences.