Theoretical analysis of vibrational spectra of molecules adsorbed on the surface of heterogeneous catalysts

The principles for choosing adsorbed complex models have been formulated. The factors for determining the differences in vibrational spectra of molecules adsorbed on the surface of various heterogeneous catalysts — the change of the adsorbed molecule itself under the action of a surface field and the contribution of the adsorption bond of adsorbed molecules with the surface site into the potential energy of an adsorbed molecule — compared with their spectra in the free state have been analyzed. The criterion of characteristicity, to determine the ratio of these two factors, has been suggested.