The diffusion of Ge dimers on the (001) surface was studied by means of scanning tunnelling microscopy. Three different diffusion pathways were identified for the dimers. These were the diffusion of on-top dimers over substrate rows, diffusion across the substrate rows, and diffusion of dimers in the trough. A previously unknown phenomenon was reported. This was the diffusion-driven concerted motion of substrate atoms. This concerted motion was a direct result of the rearrangement of substrate atoms in the neighbourhood of the trough dimer adsorption site.

Diffusion Driven Concerted Motion of Surface Atoms - Ge on Ge(001) H.J.W.Zandvliet, T.M.Galea, E.Zoethout, B.Poelsema: Physical Review Letters, 2000, 84[7], 1532-5