Optical Excitations and Applications in Novel Organic Macromolecular Aggregates

Regents Of The University Of Michigan - Ann Arbor, Ann Arbor MI

Investigators

Abstract

TECHNICAL SUMMARY An important step in the process of creating new materials for energy harvesting and nonlinear optical devices is in the understanding of the structure-function relationships based on size, geometry (cyclic, 2-dimensional), and intramolecular interactions. This proposal is directed at the development of novel organic multifunctional materials and the use of ultra-fast coherent spectroscopy to probe energy migration, nonlinear optical, and quantum interference phenomena in these materials. The PI will carry out Investigations of several novel aggregated systems will be performed. Specifically, using a combination of femtosecond spectroscopic methods such as femtosecond time-resolved fluorescence upconversion, transient absorption, transient grating, three pulse photon echo peak shift experiments complemented with those of steady state spectroscopy we will deeply investigate a variety of novel macromolecular aggregated architectures. These architectures include dendrimers with broken symmetry, new two-dimensional macromolecular structures, giant cyclic macromolecular thiophene aggregates, as well as a novel porphyrin aggregate. The PI will perform extensive modeling based on recent theoretical approaches describing exciton migration, self-trapping and the details of the excitation energy transfer between aggregated systems. NON-TECHNICAL SUMMARY The broader impact of this proposal is directed to the PI's science education activities which have been successful in encouraging young scientists of diverse backgrounds as well as the participation of women. The PI will continue to bring young scientists into the field of material science and inspire careers in science with participation in summer enrichment and mentorship programs as part of on campus and national organizations. Continued interactions with Ann Arbor and Detroit public high schools will be carried out in summer research opportunities in the PI's laboratory.