Summary: Manipulation and Control of Hydrogen Bond Dynamics in Absorbed Ice Nanoclusters
and Karina Morgenstern1
Institut fu¨r Festko¨rperphysik, Leibniz Universita¨t Hannover, Appelstrasse 2, D-30167 Hannover, Germany
Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
Materials Simulation Laboratory, London Centre for Nanotechnology and Department of Chemistry, University College London,
London WC1E 6BT, United Kingdom
(Received 12 June 2007; revised manuscript received 8 November 2007; published 24 September 2008)
Inelastic electron tunneling is used to explore the dynamics of ice nanoclusters adsorbed on Ag(111).
The diffusion of entire nanoclusters or internal hydrogen bond rearrangement can be selectively controlled
by injecting electrons either directly into the clusters themselves or indirectly (``indirect inelastic electron
tunneling'') into the substrate at distances of up to 20 nm from them; a reaction probability that oscillates
with the tip-cluster lateral distance presents evidence that surface state electrons mediate the excitation.
Density functional theory calculations reveal a strong sensitivity of the computed activation energies of
the individual processes to the applied electrical field.