title: Diffusion and dimer formation of CO molecules induced by femtosecond laser pulses.
abstract: We investigate two fundamental steps of a nonadiabatic surface process, the photo-induced movement and approach of CO molecules on the Cu(111) surface, at a hitherto unachieved single-molecule level through scanning tunneling microscope imaging. For the close approach of two CO molecules, we not only determine the nonadiabatic diffusion barrier (87 meV), but also discover a femto-second-laser-induced transient attraction (30 meV) of the usually repelling CO molecules.
authors.affiliation: Abteilung ATMOS, Leibniz Universität Hannover, Appelstrasse 2, 30167 Hannover, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Mehlhorn
authors.forename: Heiko
authors.initials: H
authors.lastname: Gawronski
authors.forename: Karina
authors.initials: K
authors.lastname: Morgenstern