First-principles simulations of the electrode|electrolyte interface

We review a direct dynamics method for the simulation of metal\water interfaces. The occupancy of on-top binding sites for water in this model as applied to a (100) surface of 'copper' is very sensitive to potential. We suggest that this may account for some previously unexplained features of X-ray data on water structure and noble metal\water interfaces. We discuss the problem of statistical fluctuations on the occupancy of such tightly bound water molecules in such simulations. Though the problem is not too serious for charged interfaces, the problem of accounting for fluctuations at zero charge can be quite formidable, as we illustrate for the (100) surface of copper. (C) 1998 Elsevier Science S.A. All rights reserved.