| Applications of ionic liquids (ILs) require a thorough understanding of the structures and reaction dynamics in these ionic solvents. The current thesis contributes to this understanding through two major projects. The first project examines the bulk structure of ILs and the second involves photo-induced bimolecular electron transfer reactions in IL solvents. In the structure project, we report structural properties for a series of silicon-substituted ionic liquids and some liquid zwitterions, comparing their structures to those of analogous "simple" ionic liquids. Structure factors of the liquids were measured using high energy X-ray diffraction and also computed from molecular dynamics simulations. As part of the simulation work, new transferable parameters for specific ILs were calibrated and added to the existing force fields. In the electron transfer project, we systematically studied the bimolecular electron transfer reactions in ILs by measuring reductive fluorescence quenching using steady-state and time-resolved methods. Molecular dynamics simulations and density-functional methods were used to explore solvation structures and electronic couplings between electron donors and acceptors. We suggest that the small-amplitude motions within contact F-Q pairs, which gate the electronic coupling, to be the limiting dynamics of intrinsic bimolecular electron transfer rates in ILs. |
