Developing a framework for the spectroscopic characterization of proton sharing and transfer

This thesis presents a series of experiments aimed at observing charge transfer in small molecular clusters. The majority of the experiments described in this work involve systems in which an excess proton is shared between two basic molecules, A·H+·B. The first studies described here concern the frequency of the first vibrational transition of the motion of the shared proton along the heavy atom axis, nusp (‖) in these clusters. While previous studies have found that nu sp(‖) is correlated strongly with the difference between the proton affinities of the two flanking molecules (DeltaPA), the studies conducted for this thesis examine an exception to this rule occurring when one of the molecules posses a large electric dipole moment. In an examination of such systems in which one of the molecules is acetonitrile, nusp(‖) has been shown to vary significantly from the DeltaPA-predicted value. Additionally, through a study performed on the H4O2+ ion, it was determined that the input of vibrational energy drives proton-transfer reactions. Expanding on this result, an investigation into charge migration along a network was performed through the incremental synthesis of chains of imidazole molecules. A final study of the effects of vibrationally mediated structural rearrangement was performed on the hydrated electron clusters (H 2O)n-. The interconversion between isomers when driven by vibrational excitation was observed to be possible.