Hopping Motion and Reaction of a Single Water Molecule on Cu(110)

Abstract

The authors studied the isolated water molecules and hydroxyl species on Cu(110) using a low-temperature scanning tunneling microscope (STM). A water molecule adsorbs on top of Cu atom and thermally hops along the atomic row at 6 K. The migration is also induced by STM via the excitation of molecule-substrate vibration. An isolated hydroxyl species, produced by dissociating a water molecule with the STM, adsorbs at the short-bridge site with its axis inclined along [001]. The orientation was found to be dynamically flipped, wherein substantial isotope effect was observed in the rate.