A general, transferable, polarizable force field for molecular simulation of protic and aprotic ionic liquids, deep eutectic solvents, electrolytes and glycols, named CL&Pol is developed. This is a major upgrade from existing fixed-charge force fields, which cannot represent with the same level of physical realism the interactions in ionic and polar media, and as such had important drawbacks to predict equilibrium, structural and transport properties of these systems. In order to compensate for the addition of explicit polarization in the form of Drude induced dipoles, the Lennard-Jones parameters of the original force field are rescaled, and the scaling factor can be evaluated either from computationally expensive quantum calculations or from the fast and general predictive scheme that we propose. Special damping functions were introduced in the force field to represent smearing of the interactions between charges and induced dipoles at a short range involving small, highly charged atoms (such as hydrogen or lithium), thus preventing the “polarization catastrophe” that can affect polarizable force fields in ionic or strongly polar systems. The new force field gives stable trajectories and shows much improved predictions of transport properties. The CL&Pol model was used to study solvation of dyes and gases in the above-mentioned systems, to describe their interfaces with nanomaterials, and to design electrolytes for energy-storage devices.
Gratuit
Disciplines