In catalysis and other surface phenomena, besides affording static influences, such as modifications in energy spectra and wave functions of atoms and molecules in chemisorbed states in contrast with those in free states, the substrate may also show its existence by participating the dynamics. The present article intends to call attention to a class of multiphonon processes which may play a role not to be ignored. The mechanism is explained throagh'the discussion of a few examples.

In catalysis and other surface phenomena, besides affording static influences, such as modifications in energy spectra and wave functions of atoms and molecules in chemisorbed states in contrast with those in free states, the substrate may also show its existence by participating the dynamics. The present article intends to call attention to a class of multiphonon processes which may play a role not to be ignored. The mechanism is explained throagh'the discussion of a few examples.