Date of Degree
Access restricted until 07/03/2019
PhD (Doctor of Philosophy)
Cheatum, Christopher M.
First Committee Member
Forbes, Tori Z.
Second Committee Member
Haes, Amanda J.
Third Committee Member
Fourth Committee Member
Quinn, Daniel M.
Proton-transfer reactions are one of the most fundamental chemical reactions. However, the chemical dynamics of these processes remain elusive due to the difficulty of modeling these reactions. Establishing an experimental model system and using infrared absorption and two-dimensional infrared (2D IR) spectroscopies as means for detection, the chemical dynamics of the protonation states that are involved in a ground-electronic-state proton-transfer reaction in solution can be determined. In this study, experimental models are established with formic acid and nitrogenous bases in a low dielectric solvent. A hydrogen bond forms between the acid and the base, which will allow for the proton to transfer between the two molecules to form the neutral and the ion-pair protonation states. The carbon-deuterium (C-D) stretch and the carbonyl (C=O) stretch of the formic acid molecule are used as the reporter groups for the 2D IR measurements. The results of the C-D stretch demonstrate that there is a high sensitivity to the deprotonation, vibrational coupling, and vibrational dynamics trends that are linked to the solute-solvent interactions. The results of the C=O stretch demonstrate a sensitivity to the deprotonation and conformational disorder in which the position of the C=O changes the dynamics of the protonation state. Although, a proton-transfer is not detected, the experimental model system provides an understanding of the features that govern the chemical dynamics of proton-transfer reactions.
Hydrogen Bonding, Infrared Spectroscopy, Proton Transfer, Two-dimensional infrared spectroscopy, Vibrational Dynamics, Vibrational Spectroscopy
xvii, 121 pages
Includes bibliographical references (pages 112-121).
Copyright © 2017 Andrea Bray Grafton
Grafton, Andrea Bray. "Vibrational dynamics of strongly hydrogen-bonded acid-base complexes in solution." PhD (Doctor of Philosophy) thesis, University of Iowa, 2017.