Electronic and vibrational excitation of single molecules with a scanning tunneling microscope

The electronic and vibrational excitations of single acetylene, pyridine, and benzene molecules on Cu(001) were studied by scanning tunneling microscopy at 9 K. Electrons of 0–5 eV were used to induce dissociation, desorption, diffusion, rotation, and vibrational excitation of these molecules. The dissociation products were characterized by imaging, single molecule vibrational spectroscopy, and rotational excitation. The STM is shown to be a very versatile tool for inducing a molecule to explore its excited state potential energy surface and describing the possible results.