Rotation of a single acetylene molecule on Cu(001) by tunneling electrons in STM.
We study the elementary processes behind one of the pioneering works on scanning tunneling microscope 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 density functional theory 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).
A. M. Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow 119991, Russia.
Yulia E
YE
Shchadilova
Sergei G
SG
Tikhodeev
Magnus
M
Paulsson
Hiromu
H
Ueba