title: Direct observation of the conformational transitions of single pyridine molecules on a Ag(110) surface induced by long-range repulsive intermolecular interactions.
abstract: The transition between two conformations of pyridine molecules adsorbed on a Ag(110) surface at 13 K was investigated by performing single-molecule manipulation at a very low coverage and the track-imaging of pyridines for various surface coverages using a variable low-temperature scanning tunneling microscope. A single tilted conformer was converted to an upright conformer when another coadsorbed tilted pyridine molecule approached to within ∼2 nm. The conversion probability depends on the molecular separation. The tilted conformers that are prevalent at a very low coverage were converted to upright conformers with an increasing surface coverage. The minimum molecular separation before this transition is induced was determined to be 2.2 nm using molecular track-imaging and statistical analysis of the pyridine separation as a function of the molecular coverage. The conformation transition was attributed to substrate-mediated long-range repulsive interactions between the pyridine molecules, which are produced by charge redistribution that occurs upon pyridine adsorption on the silver surface.
authors.affiliation: Department of Chemistry and Bioactive Material Sciences and Research Institute of Physics and Chemistry, Chonbuk National University, Jeonju 561-756, South Korea.
authors.forename: Insup
authors.initials: I
authors.lastname: Lee
authors.affiliation: Jeonju Center, Korea Basic Science Institute, Jeonju 561-756, South Korea.
authors.forename: Seungbae
authors.initials: S
authors.lastname: Son
authors.affiliation: Department of Chemistry and Bioactive Material Sciences and Research Institute of Physics and Chemistry, Chonbuk National University, Jeonju 561-756, South Korea.
authors.forename: Taeho
authors.initials: T
authors.lastname: Shin
authors.affiliation: Department of Chemistry and Bioactive Material Sciences and Research Institute of Physics and Chemistry, Chonbuk National University, Jeonju 561-756, South Korea.
authors.forename: Jae R
authors.initials: JR
authors.lastname: Hahn