The activation energies and pre-factors which governed various self-diffusion processes on (110) were estimated by using the embedded-atom approximation for surface energetics. A detailed investigation, which included the contribution made by friction, showed that the pre-factors for concerted- or exchange-type diffusion, perpendicular to the close-packed rows, were comparable to those which governed direct single-atom hops along the rows.

L.D.Roelofs, B.J.Greenblatt, N.Boothe: Surface Science, 1995, 334, 248-56