PROBING THE NATURE OF MOLECULAR CHEMISORPTION USING RAIRS

Reflection absorption infrared spectroscopy has now established itself as a powerful and versatile technique for monitoring molecular adsorption at defined single crystal metal surfaces. This paper discusses the success of the technique in providing a wide range of information, including the identification of hydrocarbon species and monitoring molecular adsorbate-induced surface reconstructions. The use of IR spectroscopy in determining the nature of chemisorbed species is discussed in the light of recent structural investigations questioning the validity of vibrational "fingerprints". Finally, the need for high resolution capability is demonstrated by new intramolecularly decoupled IR experiments which allow individual types of CH bonds in complex hydrocarbons to be identified.