Optical properties of molecules chemisorbed on the Ni (111) surface

The adsorption of a series of molecules on Ni (111) is studied by UV visible spectroscopic ellipsometry. The spectra were analyzed within a simple dielectric model. Chemisorption of molecules on the Ni (111) surface produces a peak in the overlayer optical response at 4.2 eV. This absorption peak is attributed to the selective enhancement of bulk interband excitations resulting from perturbations of the metal orbitals upon chemisorption.