Structure of Water at Metal Surfaces

The microscopic structure of water at the solution/metal interface has been the focus of a large body of literature, and excellent reviews have been published summarizing the extensive knowledge gained from experiments, statistical mechanical theories of varied sophistication, and Monte Carlo and molecular dynamics computer simulations. To keep this chapter to a reasonable size, we limit ourselves to a brief summary of the main results and to a sample of the type of information that can be gained from computer simulations. 

The structure of water at interfaces in general, and at the metal surface in particular, is determined by a number of factors  

The specific interactions between a water molecule and the metal atoms. The pair interaction H2O-M is further modified by the metal surface lattice structure and by defects and the electrons in the metal, as discussed earlier. 

The tendency of water molecules to orient in such a way as to maximize hydrogen bonding with other water molecules at the interface and in the vicinity of the interface. 

Any external forces due to adsorbed molecules and charges on the metal surface. 

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