title: Lateral hopping of molecules induced by excitation of internal vibration mode.
abstract: We demonstrate electron-stimulated migration for carbon monoxide (CO) molecules adsorbed on the Pd(110) surface, which is initiated by the excitation of a high-frequency (HF) vibrational mode (C-O stretching mode) with inelastic tunneling electrons from the tip of scanning tunneling microscopy. The hopping phenomenon, however, cannot be detected for CO/Cu(110), even though the hopping barrier is lower than in the CO/Pd(110) case. A theoretical model, which is based on the anharmonic coupling between low-frequency modes (the hindered-translational mode related to the lateral hopping) and the HF mode combined with electron-hole pair excitation, can explain why the hopping of CO is observed on Pd(110) but not on Cu(110).
authors.affiliation: RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Komeda
authors.forename: Y
authors.initials: Y
authors.lastname: Kim
authors.forename: Maki
authors.initials: M
authors.lastname: Kawai
authors.forename: B N J
authors.initials: BN
authors.lastname: Persson
authors.forename: H
authors.initials: H
authors.lastname: Ueba