Adatom diffusion on a Si(100) surface was studied at 1000 to 1300K using long-term empirical molecular dynamics simulations. Exchange was found to occur with non-negligible frequency (1/30 to 1/80) as often as hopping occurred. This had only a minor effect upon diffusion parallel to the dimer row, but had a major effect upon that perpendicular to the dimer row. Various complex exchange events, involving up to three surface atoms, were observed.

Molecular Dynamics Study of Adatom Diffusion on Si(100) Surface - Importance of the Exchange Mechanism. Iijima, T., Sugino, O.: Surface Science, 1997, 391[1-3], L1199-204