Ultrahigh vacuum chamber for Raman studies of gases adsorbed on metals.

An ultrahigh vacuum chamber is described which is being used to study laser Raman spectra associated with gas adsorption on clean metal surfaces. The system enables sample temperatures from -85 degrees to 600 degrees C to be obtained, and besides surface cleaning capabilities associated with high-temperature oxidation or reduction, it incorporates an Ar(+) sputter gun for surface cleaning. Initial experiments of CO+H(2) adsorption on crystalline Ni surfaces are described and the effects of H(2) and O(2) exposure shown for the 80 cm(-1) band which results from CO+H(2) adsorption.