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Molecular dynamics simulation of reverse micelles of a cationic surfactant and water clusters in n -octane is performed. The main structural and thermodynamic characteristics of the systems are obtained. On average, the micelles have a spherical shape. The partial ion distribution densities virtually coincide, indicating the formation of stable ion pairs. The local profiles of the component distribution densities make it possible to establish that both water and oil slightly penetrate into the region where the hydrophobic portion of the surfactant is located. Separate cation-anion complexes dissolve in the aqueous cavity of a micelle. The hydration shells of the ions overlap; at the same time, the first hydration shell contains up to three water molecules. The energy contributions of each of the components to their force interaction are characterized in detail. The principal contribution to the internal energy for micelles is due to electrostatic interaction between the surfactant molecules. The local normal pressure is calculated, and its value is used to estimate the effective surface tension for the systems in question.

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Reverse micelles of Aerosol OT in the medium of supercritical carbon dioxide have been simu lated by the molecular dynamics method. For the first time, a micelle in ternary water-Aerosol OT-super critical CO 2 has been simulated by describing the surfactant and the supercritical liquid in terms of the coarse grained approach. It has been shown that the structural and energetic characteristics of the micelle are, with a good accuracy, described within the framework of simplified models.

The literature data are reviewed on molecular simulation of reverse micelles and water in oil microemulsions by the molecular dynamics and Monte Carlo methods. Different models of reverse micelles from a spherical cavity with an impenetrable wall to an atomistic ensemble of surfactant molecules are con sidered. The main structural and thermodynamic properties, as well as the dynamics of micelle components are considered. The results are compared with the data obtained using both a single model and models of dif ferent levels.

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