Energetics and Dynamics of Si Ad-Dimers on Si(001)

Abstract

The energetics and dynamics of Si ad-dimers on Si(001) have been investigated by total-energy calculations and scanning tunneling microscopy. Several dimer configurations and a thermally activated rotational mode of the dimer on top of a dimer row are theoretically predicted and experimentally identified. The frequency of occurrence of the different dimer configurations suggests a likely pathway for monomer diffusion.