(355e) A Monte Carlo Simulation Study On The Wetting Behavior Of Water On Graphite Surface


We report the wetting transition of water on graphite surface observed from molecular simulations. We calculate adsorption isotherms of water on graphite using grand canonical Monte Carlo simulations combined with multiple histogram reweighting, based on the empirical potentials of SPC/E for water, 10-4-3 van der Waals model and a recently developed induction and multipolar potential for water and graphite. Our results show that wetting transition of water on graphite occurs at 475 to 480 K, and the surface critical temperature lies in 505 to 510 K. The calculated wetting transition temperature agrees quantitatively with a previously predicted value using a simple model. The observation of the coexistence of stable and metastable states at temperatures between the wetting transition temperature and surface critical temperature indicates that the transition is first order. We propose a simple relationship between the wetting temperature and the solid-fluid interaction to explain the sensitive dependence of the wetting behavior on the solid-fluid potential.