Abstract
The processes of vibrational relaxation, i.e., of the vibrational excitation and deexcitation of molecules, are known to play the key role in providing them with the energy needed to participate in chemical reactions. At present numerous experimental data are known concerning vibrational relaxation in gases, liquids, and solids. In contrast, vibrational relaxation on surfaces is much less studied. Fairly detailed experimental data have been obtained for vibrational relaxation processes with physically adsorbed small molecules [1–10]. At the same time, theoretical works in this field are rather numerous. However, most of these works cover only some specific aspects of the vibrational relaxation on surfaces rather than this phenomenon as a whole.