Summary: cð2 Â 2Þ Water-Hydroxyl Layer on Cu(110): AWetting Layer Stabilized by Bjerrum Defects
and Angelos Michaelides2
Surface Science Research Centre and Department of Chemistry, University of Liverpool,
Oxford Street, Liverpool, L69 3BX, United Kingdom
London Centre for Nanotechnology and Department of Chemistry, University College London, London WC1E 6BT, United Kingdom
Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany
(Received 11 November 2010; published 24 January 2011)
Understanding the composition and stability of mixed water-hydroxyl layers is a key step in describing
wetting and how surfaces respond to redox processes. Here we show that, instead of forming a complete
hydrogen bonding network, structures containing an excess of water over hydroxyl are stabilized on Cu
(110) by forming a distorted hexagonal network of water-hydroxyl trimers containing Bjerrum defects.
This arrangement maximizes the number of strong bonds formed by water donation to OH and provides
uncoordinated OH groups able to hydrogen bond multilayer water and nucleate growth.