THE STILLINGER-DAVID WATER MODEL

The functional form of the modified Stillinger-David potential is as follows 

For water molecules, there is a three-body term of the form 

IRON-WATER AND SILICON-WATER POTENTIALS AND THE BEHAVIOR OF AND Si IN THE GAS PHASE AND IN AQUEOUS SOLUTION 

Both the Si and Fe potentials yielded qualitatively reasonable behavior when used in a simulation of a single aqueous ion in a solution of 216 water molecules. For the Fe system, the potential 

The next level of complexity is to create a surface from the bulk material. First, it is necessary to choose the type of model to be used to represent a surface. There are two possible choices (1) a semi-infinite surface (Jones et al. 2000) or (2) a slab. The semi-infinite model uses a two-region approach, whereas the slab model uses 2-D periodic Ewald methods to treat long-range forces. In either case, it is necessary to demonstrate convergence in the former case, with respect to the partitioning of the two regions in the latter case, with respect to the thickness of the slab. 

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