Detailed structural analysis of a 2 molal aqueous rubidium bromide solution: A combined molecular dynamics and Reverse Monte Carlo approach

Abstract

A detailed study of the microscopic structure of an electrolyte solution, 2 molal RbBr in water, is presented. We combine one total scattering structure factor from neutron diffraction and 7 partial radial distribution functions from molecular dynamics (MD) simulations in one single structural model, generated by Reverse Monte Carlo (RMC) modeling. From the particle coordinates, distribution of the number of first neighbors, as well as angular correlation functions could be calculated. It is shown that the hydration shells of both cations and anions are rather diffuse whereas water molecules surround each other more orderly, thus maintaining a recognizable network of hydrogen bonds.