CAS: Highly Interacting Panchromatic Push-Pull Systems: Symmetry Breaking and Quantum Coherence in Electron Transfer

With support from the Chemical Structure, Dynamics, and Mechanisms A (CSDM-A) program in the Division of Chemistry, a research team at the University of North Texas is developing a novel class of molecular push-pull systems capable of panchromatic light capture and strong intramolecular charge transfer in molecular materials highly pursued for numerous optoelectronic, light-energy harvesting, and optical sensor applications. The design and synthesis of this class of molecular systems will enable the exploration of photochemical phenomena such as symmetry-breaking charge transfer and quantum coherence in electron transfer. The ultrafast charge transfer phenomenon in these systems will be investigated using an array of spectral, electrochemical, computational, and time-resolved spectroscopic methods covering wide spatial and temporal regions. The project will provide extensive teaching and training for graduate and undergraduate students. The technical knowledge, problem-solving abilities, and communication skills learned through participating in the project are expected to contribute to the development of the nation's scientific workforce in energy efficiency and clean energy technologies. Outreach efforts will contribute to a highly diversified research group and collaboration with the Elm Fork Education Center to enhance general science education are also part of the project. By constructing multi-modular push-pull systems comprised of highly interacting, powerful donor and acceptor entities, the North Texas research team will address several scientific challenges. These include: (i) developing wide-band capturing intramolecular charge transfer complexes capable of producing charge-separated states upon photoexcitation; (ii) developing nanocarbon- (fullerene, endohedral fullerene, and single-walled carbon nanotube) derived near infrared light capturing charge transfer complexes; (iii) probing redox and photochemical phenomenon such as ‘intervalence charge transfer’ and ‘symmetry breaking charge transfer’ in multi-modular complexes having quadrupolar or octupolar ground states and (iv) observing the process of ‘quantum coherence in promoting charge transfer’ and investigating underlying mechanistic details while generating structure-activity relationships. The outcomes of this research project have the potential for broad impact across many disciplines of science. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.