THE INFLUENCE OF LONG-RANGE ELECTROSTATIC FORCES ON STATIC PROPERTIES OF A QUASI-STOCKMAYER FLUID

This paper discusses the implementation of the reaction field method previously developed [1] for inhomogeneous fluids, and presents results for selected properties of a dipolar model fluid at a liquid-gas interface. To implement the reaction field, a fit function based on the image charge approach is introduced. The fit function features eight image charges placed at uniquely determined points inside a dielectric slab of infinite extent in the x, y-plane and fixed height in the z-direction in which the molecular dynamics (MD) simulation sample is embedded. In addition to the image charges, a set of seven scaling parameters is introduced to take care of the effect of truncating the image charge expansion. Based upon this approach, MD runs are performed with and without an applied reaction field. These runs reveal that, similar to what is known for dipolar bulk fluids, purely structural properties remain unaffected while dielectric properties are very sensitive to the reaction field.