AVS 53rd International Symposium
    Surface Science Tuesday Sessions
       Session SS-TuP

Paper SS-TuP4
Partially Dissociated Water Clusters on Ru(0001) Studied by Scanning Tunneling Microscopy

Tuesday, November 14, 2006, 6:00 pm, Room 3rd Floor Lobby

Session: Surface Science Poster Session
Presenter: T.K. Shimizu, Lawrence Berkeley National Laboratory and University of California at Berkeley
Authors: T.K. Shimizu, Lawrence Berkeley National Laboratory and University of California at Berkeley
A. Mugarza, Lawrence Berkeley National Laboratory and Institut de Ciencia de Materials de Barcelona, Spain
J. Cerda, Instituto de Ciencia de Materiales de Madrid, CSIC, Spain
D.F. Ogletree, Lawrence Berkeley National Laboratory
M. Salmeron, Lawrence Berkeley National Laboratory
Correspondent: Click to Email
Individual molecules in partially dissociated water clusters have been imaged at 6K using a home-built low temperature scanning tunneling microscope (STM). After annealing the surface with pre-adsorbed oxygen and water above 140 K, elongated clusters with enhanced contrast at the perimeter were observed. By comparing the experimental data with STM simulations, we conclude that the clusters consist of mixed water and hydroxyl molecules lying flat. The presence of pre-adsorbed oxygen prevents the formation of a perfect hexagonal network inside the clusters and affects their overall shapes. Hydrogen atoms were observed both inside and outside the clusters, the latter reacting with the pre-adsorbed oxygen to form hydroxyl.