Rotation of a single acetylene molecule on Cu(001) by tunneling electrons in STM

Abstract

We study the elementary processes behind one of the pioneering works on STM controlled reactions of single molecules [Stipe et al., Phys. Rev. Lett. 81, 1263 (1998)]. Using the Keldysh-Green function approach for the vibrational generation rate in combination with DFT calculations to obtain realistic parameters we reproduce the experimental rotation rate of an acetylene molecule on a Cu(100) surface as a function of bias voltage and tunneling current. This combined approach allows us to identify the reaction coordinate mode of the acetylene rotation and its anharmonic coupling with the C-H stretch mode. We show that three different elementary processes, the excitation of C-H stretch, the overtone ladder climbing of the hindered rotational mode, and the combination band excitation together explain the rotation of the acetylene molecule on Cu(100).

5+5 pages, 4+2 figures

References in corpus (2)

• Relation between inelastic electron tunneling and vibrational excitation of single adsorbates on metal surfaces
• From tunneling to contact: Inelastic signals in an atomic gold junction

Cited by in corpus (3)

• In memoriam Leonid V. Keldysh
• Modeling the metastable dynamics of correlated structures
• Isotope effect in acetylene C${}_2$H${}_2$ and C${}_2$D${}_2$ rotations on Cu(001)