23 research outputs found
Recommended from our members
Optical Properties of Molecules Chemisorbed on the Ni(111) Surface
The adsorption of a variety of molecules on Ni(111) is studied UV/visible spectroscopic ellipsometry. The spectra were analyzed within a simple dielectric model. The absorption spectra of annealed, thin, condensed layers of pyrazine, pyridine, and naphthalene on the Ni(111) surface resemble bulk crystal spectra, indicating minimal perturbations due to the metal substrate. Chemisorption of molecules on the Ni(111) surface produced enhanced absorption between 2800{Angstrom} and 3100{Angstrom}. The wide range of adsorbate properties and surface chemistry suggest a modification of the optical response of the metal upon chemisorption. This enhanced optical absorption is attributed to nonvertical interband transitions made possible by loss of translational invariance at the surface