PNNL

Abstract

The electron density profiles and the corresponding surface structures of an aqueous interface of SrCl2 salt solution were computed using molecular dynamics simulations. We used both polarizable and non-polarizable potential models to describe molecular interactions. The results demonstrate that the polarizable models captured the essential features of the x-ray reflectivity experimental data while the corresponding non-polarizable models could not. While there is qualitative agreement in the shape of the x-ray reflectivity curve, we find that quantitative agreement is still forthcoming. We suggest that improved agreement can be achieved if the contribution of Sr2+ ions to the total electron density profile is reduced, but not eliminated. This work was performed at Pacific Northwest National Laboratory under the auspices of the Division of Chemical Sciences, Office of Basic Energy Sciences, U.S. Department of Energy (DOE). Pacific Northwest National Laboratory is operated by Battelle for the DOE.