title: Repulsion-Induced Surface-Migration by Ballistics and Bounce.
abstract: The motion of adsorbate molecules across surfaces is fundamental to self-assembly, material growth, and heterogeneous catalysis. Recent Scanning Tunneling Microscopy studies have demonstrated the electron-induced long-range surface-migration of ethylene, benzene, and related molecules, moving tens of Angstroms across Si(100). We present a model of the previously unexplained long-range recoil of chemisorbed ethylene across the surface of silicon. The molecular dynamics reveal two key elements for directed long-range migration: first 'ballistic' motion that causes the molecule to leave the ab initio slab of the surface traveling 3-8 Å above it out of range of its roughness, and thereafter skipping-stone 'bounces' that transport it further to the observed long distances. Using a previously tested Impulsive Two-State model, we predict comparable long-range recoil of atomic chlorine following electron-induced dissociation of chlorophenyl chemisorbed at Cu(110).
authors.affiliation: Lash Miller Chemical Laboratories, Department of Chemistry and Institute of Optical Sciences, University of Toronto , 80 St. George Street, Toronto, Ontario M5S 3H6, Canada.
authors.forename: Si Yue
authors.initials: SY
authors.lastname: Guo
authors.affiliation: Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge, CB2 1EW, United Kingdom.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Jenkins
authors.affiliation: Department of Physics and Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-nano Devices, Renmin University of China , Beijing 100872, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Ji
authors.affiliation: Lash Miller Chemical Laboratories, Department of Chemistry and Institute of Optical Sciences, University of Toronto , 80 St. George Street, Toronto, Ontario M5S 3H6, Canada.
authors.forename: Zhanyu
authors.initials: Z
authors.lastname: Ning
authors.affiliation: Lash Miller Chemical Laboratories, Department of Chemistry and Institute of Optical Sciences, University of Toronto , 80 St. George Street, Toronto, Ontario M5S 3H6, Canada.
authors.forename: John C
authors.initials: JC
authors.lastname: Polanyi
authors.affiliation: Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge, CB2 1EW, United Kingdom.
authors.forename: Marco
authors.initials: M
authors.lastname: Sacchi
authors.affiliation: Lash Miller Chemical Laboratories, Department of Chemistry and Institute of Optical Sciences, University of Toronto , 80 St. George Street, Toronto, Ontario M5S 3H6, Canada.|Department of Physics and Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-nano Devices, Renmin University of China , Beijing 100872, China.
authors.forename: Chen-Guang
authors.initials: CG
authors.lastname: Wang
keywords: ab initio calculations; molecular dynamics; surface chemistry; surface-migration