EXPERIMENTAL AND THEORETICAL-STUDY OF THE ROTATION OF SI AD-DIMERS ONTHE SI(100) SURFACE

Scanning tunneling microscopy measurements and first principles densit y functional theory calculations are used to study the rate of the rot ational transition of Si ad-dimers on top of the surface dimer rows of Si(100). The rotation rate and the relative population of the two sta ble orientations of the ad-dimers are measured as a function of the ap plied electric held to extract the zero-field behavior. The measured r elative stability of the two configurations is used to test the accura cy of various functionals for density functional theory calculations.