Surface diffusion of adsorbates

The review covers studies of the surface diffusion of adsorbed species on single crystal substrates. Experimental techniques employed in investigations of the surface diffusion of adsorbates are discussed. Emphasis is placed on the analysis of data obtained at considerable degrees of coverage. These results demonstrate a close interrelation between surface diffusion and phase transitions in adsorbed layers. Possible mechanisms of surface diffusion are considered taking into account the structure of adsorbed layers. Findings on the effect of electric fields on surface diffusion processes are reviewed.