Water−Graphite Interaction and Behavior of Water Near the Graphite Surface

Based on MP2 level electronic structure calculations of the binding energy and lowest energy conformation of water−acene complexes [Feller, D.; Jordan, K. D. J. Phys. Chem. A 2000, 104 (44), 9971−9975], three water−graphite model potentials are suggested and tested in grand canonical Monte Carlo simulations of the behavior of water confined between two parallel graphite sheets. It is shown that the thermodynamics and structure of the water−graphite interfacial region are extremely sensitive to the range and orientation dependence of the model potential. This casts doubt on the results of previous molecular dynamics simulations using orientation-independent potentials and standard atomistic force fields. All of the three suggested potentials predict that the water monolayer compressed between two parallel graphite surfaces does not experience capillary evaporation and offers only slight resistance to shear. This explains why water can serve as a lubricant in the friction of graphitic carbons.