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Molecular dynamics simulations are used to study the response of a room temperature molten salt to an external electric field when it is confined to a nanoslit. The spectrum of charge density fluctuations in the bulk is used to describe the relaxation of the polarization in the confined system.

The effects of varying the relative weights of the Lennard-Jones and Coulombic contributions to the energy of the SPC/E model on its water like structural, dynamic, and thermodynamic anomalies are investigated. The results suggest that for a liquid to show negative thermal expansion and anomalous density dependence in its transport properties, it must have a local structure that differs from and is inconsistent with simple Lennard-Jones type spherical symmetry.

The simulations of a model system of charged spherical ions in the ionic liquids dimethylimidazolium chloride ([dmim][Cl]), dimethylimidazolium hexafluorophosphate ([dmim][P[F.sub.6]]) and the polar liquid acetonitrile (MeCN) are used for examining the applicability of Marcus theory to electrochemical half-cell redox processes in these liquids. The similarities between the different types of solvent are attributed to the essentially long-range nature of the relevant interactions and the effectiveness of the screening of the ion potential.

An alternative explanation of the size-dependent maximum in ion mobility in water in terms of the levitation effect is proposed, which accounts for the observed size-dependent maximum in the ion mobility of guest diffusion in porous media. As in the levitation effect, the friction coefficient, the potential energy fluctuations, and the activation energy are found to be minima for particles with maximum self diffusivities similar to the guest diffusion in zeolites.

The microscopic structural and dynamic properties of 1,3-dimethylimidazolium chloride and 1,3-dimethylimidazolium hexafluorophospate with water are investigated. The analysis of both the local structure and the dynamics of the mixtures reveal that at low concentrations water molecules are isolated or exist in small independent clusters.

There has been extensive study of ion mobilities in polar solvents in the bulk phase, and it is suggested that the Stokes' law breaks down in the case of small ions in highly polar solvents. Experiments show separate curves for cation and anion mobilities and it is suggested that the asymmetric charge distribution of the solvent molecule may explain this. A computer simulation study was undertaken of contributions of the frictional force on ions in aqueous solution at 25 deg C at infinite dilution.

Molecular dynamics simulation using the simple point charge model for water at 25 degrees Centigrade was used to study the mobilities of the metal cations Li+, Na+, K+, Rb+, Cs+ and Ca2+ and the halides F-, Cl-, Br- and I- at infinite dilution. The mobilities of Li+, Na+, K+, Rb+ and F- were found to increase on discharge, while Cl, Br and I showed smaller mobilities. Results also provide information on the solvation structure and dynamics of the individual cations and anions relative to their mobilities.