Multi-property Fitting and Parameterization of a Coarse Grained Model for Aqueous Surfactants

Wataru Shinoda, Russell DeVane, and Michael L. Klein

Molecular Simulation 33 27-36 (2007)

A new systematic approach to build coarse-grained (CG) molecular models for surfactants/water systems is proposed. A step-by-step approach using several molecular systems for the parameterization makes the CG model versatile and transferable. The intramolecular bond potentials are determined to reproduce the bond and angle distributions obtained from all-atom molecular dynamics simulations. A careful choice of the potential function for nonbonded interactions is essential for better structural properties. Density and surface/interfacial tension data are used for parameter fitting, because these thermodynamic properties are of key importance in characterizing the selforganized surfactant structure. Solvation (hydration) and transfer free energies, which play an essential role in determining the partition of solute molecules, are also taken into account in the model.