Hydrogen-Bonded Clusters: A Study of the Elusive Anisole-Ammonia and Anisole-Water 1:1 Complexes
Date of Award
Master of Science (MS)
Reid, Scott A.
The hydrogen bond is one of the most important and versatile interactions found in most subsets of chemistry and biology. This interaction is responsible for reactions and characteristic properties of the systems in thereof. This interaction is just one of several available non-covalent interactions that can occur and over the past several decades of molecular spectroscopy studies, the definition of the hydrogen bond has become broader compared to the “classic” definition. To accurately study the hydrogen-bonding in these systems can be quite challenging due to the size and complexity of the molecules involved, as well as the other interactions that may play a role. In order to study these interactions, model systems containing the isolated conditions for hydrogen bonding similar to their real-world counterparts have been of great use. By studying the strength, geometric orientation, and spectral features of these systems, these types of interactions are better understood. Of the model systems involved, those containing ammonia and water have been widely studied due to the critical role of the two solvents across all of chemistry, especially biochemistry. In the past few decades, the anisole-ammonia and anisole-water 1:1 complexes, two potential candidates for hydrogen bonding, have been studied. However, these studies have been mostly comprised of initial experimental investigations and low-level theoretical calculations. This leaves some ambiguity as to the exact strength and binding motifs of these complexes. The focus of this thesis is to identify the shortcomings of the recent literature and answer some of the remaining questions. The ground-state experimental binding energy for the anisole-ammonia complex is reported for the first time via 2-color-resonant 2-photon ionization (2CR2PI) spectroscopy. Through several high-level DFT calculations, the ground-state structure and binding energy are reported and compared to previous literature. Also, the same plethora of theoretical methods were used to explore the complex in the cation-radical state for the first time. Similarly, the same theoretical investigations were employed to study the ground-state and cation radical structure and binding energy were studied for the anisole-water 1:1 complex. The results obtained were then compared to the previous studies.