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Updated: Aug 11, 2026

High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy
Published on: June 28, 2016
Single-molecule reactions and spectroscopy via vibrational excitation
Maki Kawai1, Tadahiro Komeda, Yousoo Kim
1RIKEN (The Institute of Physical and Chemical Research), 2-1 Hirosawa, Wako, Saitama 351-0198, Japan. maki@postman.riken.go.jp
Abstract:
Inelastic tunnelling spectra of single C4 hydrocarbon molecules adsorbed on the Pd(110) surface are presented. Experimental evidence is given that the symmetry of the molecular orbital into which the tunnelling electron first enters determines which vibrational modes are excited. The action spectrum for cis-2-butene exhibits most of the vibrational modes that are expected to be excited except for nu (C[double bond]C), which may be because the molecule is pi bonded to the substrate, thus making the lifetime of the excited state short.
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