The proposed experiments address a number of issues particularly germane to excited-state processes and chemistry. The quantum efficiencies of the luminescence and the photochemical reactions of aminoarenes and aryl amides, which have recently been shown to be sensitive to the position of the amino substituent, will be correlated with precursor structure to provide insights into structural relaxation of the excited state, and how that relaxation influences subsequent photophysical and photochemical processes. A separate measure of the electronic influence on excited state behavior will be achieved by measuring the photocyclizations of the amino-substituted stilbenes, while new information regarding photoinduced electron transfer and intramolecular charge-transfer states will be provided through studies of novel donor-acceptor pairs. With this award, the Organic and Macromolecular Chemistry Program supports the research of Professor Frederick D. Lewis of the Department of Chemistry at Northwestern University. Professor Lewis' research will provide unique insights into the structural changes that accompany electronic excitation and how these changes, separate from concurrent electronic changes, influence the subsequent reactivity and relaxation of intramolecular charge-transfer states. The research will introduce undergraduate, graduate and postdoctoral students to steady-state and time-resolved photochemical techniques, and their application to elucidating fundamental excited-state processes.
