title: Coverage and nearest-neighbor dependence of adsorbate diffusion.
abstract: We present data on the coverage and nearest-neighbor dependences of the diffusion of CO on Cu(111) by time-lapsed scanning tunneling microscope (STM) imaging. Most notable is a maximum in diffusivity of CO at a local coverage of one molecule per 20 substrate atoms and a repulsion between CO molecules upon approach closer than three adsites, which in combination with a less pronounced increase in potential energy at the diffusion transition state, leads to rapid diffusion of CO molecules around one another. We propose a new method of evaluating STM-based diffusion data that provides all parameters necessary for the modeling of the dynamics of an adsorbate population.
authors.affiliation: Pierce Hall, University of California-Riverside, Riverside, CA 92521, USA.
authors.forename: Kin L
authors.initials: KL
authors.lastname: Wong
authors.forename: Bommisetty V
authors.initials: BV
authors.lastname: Rao
authors.forename: Greg
authors.initials: G
authors.lastname: Pawin
authors.forename: Erick
authors.initials: E
authors.lastname: Ulin-Avila
authors.forename: Ludwig
authors.initials: L
authors.lastname: Bartels