Summary: To Wet or Not to Wet? Dispersion Forces Tip the Balance for Water Ice on Metals
and Angelos Michaelides1
London Centre for Nanotechnology and Department of Chemistry, University College London, London WC1E 6BT, United Kingdom
Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 46, D-14195 Berlin, Germany
(Received 15 November 2010; published 11 January 2011)
Despite widespread discussion, the role of van der Waals dispersion forces in wetting remains unclear.
Here we show that nonlocal correlations contribute substantially to the water-metal bond and that this is an
important factor in governing the relative stabilities of wetting layers and 3D bulk ice. Because of the
greater polarizability of the substrate metal atoms, nonlocal correlations between water and the metal
exceed those between water molecules within ice. This sheds light on a long-standing problem, wherein
common density functional theory exchange-correlation functionals incorrectly predict that none of the
low temperature experimentally characterized icelike wetting layers are thermodynamically stable.
DOI: 10.1103/PhysRevLett.106.026101 PACS numbers: 68.43.Bc, 68.43.Fg, 82.65.+r
Water covers almost all solid surfaces under ambient
conditions. As such, interfacial water is of crucial impor-