RAIRS description

Conventionally RAIRS has been used for both qualitative and quantitative characterization of adsorbed molecules or films on mirror-like (metallic) substrates [4.265]. In the last decade the applicability of RAIRS to the quantitative analysis of adsorbates on non-metallic surfaces (e.g. semiconductors, glasses [4.267], and water [4.273]) has also been proven. The classical three-phase model for a thin isotropic adsorbate layer on a metallic surface was developed by Greenler [4.265, 4.272]. Calculations for the model have been extended to include description of anisotropic layers on dielectric substrates [4.274-4.276]. 

S-ProUne on Cu(110) From the section above, it can be seen that a general description of the amino acid species present in an adsorbed overlayer can be teased out from the RAIRS data, aided by a qualitative application of the metal surface selection rule. However, a major challenge exists for the field, namely, can one map the conformation and bonding interaction of each molecule to the surface. 

The DFT calculation yielded a list of the calculated frequencies, absolute RAIRS intensities, and description of the 70 normal modes possessing frequencies higher than 600 cm [93], Table 3.4.1.6 compares the main bands observed in the experimental RAIR spectrum with the calculated spectrum and the description of the normal modes giving rise to the vibrational bands. The major spectral regions of interest are described in more detail below. 

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