Abstract

Raman spectroscopy is an exceptionally powerful probe of the structures and reactions of molecules on surfaces with applications in catalysis, corrosion, electrochemistry and electronic materials. Recent advances in technology have resulted in submonolayer sensitivity for a wide variety of molecules adsorbed on low surface area single crystal substrates which may be metals, semiconductors or dielectrics. This sensitivity, which does not require any source of either surface or resonance enhancement, has been achieved through an understanding of the underlying physics and careful implementation of the experimental design. The physics of surface Raman scattering will be discussed as it determines both the experimental geometries and surface selection rules. As an example of the chemical utility of the technique, the adsorption and reaction of pyromellitic dianhydride and oxydianiline to form polyimide will be discussed. Finally, special considerations relevant to electrochemistry will be described and a few comments will be made on the chemical mechanism of surface-enhanced Raman scattering.

© 1990 Optical Society of America