Molecular dynamics and hybrid Monte Carlo simulations of a sodium bis(2-ethylhexyl)-sulfosuccinate reverse micelle

Abstract

The bis(2-ethylhexyl)sulfosuccinate (AOT) reverse micelle is a nanometer-sized quasispherical aggregate that can dissolve water in its interior. This feature makes a reverse micelle a valuable model system for the study of “hydration water”, i.e. water confined in the proximity of polar and ionic groups. We present a first study of the structural and thermodynamical properties of a system formed by 2048 CCl₄ molecules in which an AOT reverse micelle, including its internal hydration water and Na⁺ counterions, is contained. CCl₄ equilibrium configurations are obtained from a very long hybrid Monte Carlo simulation of a cubic box of 256 CC1₄ molecules which is then duplicated in all three dimensions. The whole system is successively equilibrated using a standard molecular dynamics simulation algorithm.