PNNL

Abstract

In this paper, we compute the structural factor and corresponding x-ray reflectivity of the aqueous interface of RbBr salt solutions using molecular dynamics techniques and polarizable and non-polarizable potential models. Our computed electron and number densities clearly demonstrate that the polarizable Br- anions are concentrated at the water surface, while the non-polarizable Br- anions are depleted from the surface. This observation contradicts a recently published conclusion that was based on x-ray reflectivity measurements. This work was supported by the U.S. Department of Energy's (DOE) Office of Basic Energy Sciences, Chemical Sciences program. The Pacific Northwest National Laboratory is operated by Battelle for DOE.