University of Waterloo
200 University Avenue West
Waterloo, Ontario, Canada N2L 3G1
Phone: (519) 888-4567 ext 32215
Fax: (519) 746-8115
Miguel A. Garcia-Garibay
Professor and Chair
Department of Chemistry and Biochemistry
University of California, Los Angeles
While the chemical amplification of excited state processes is rare, it would be highly desirable for a wide range of applications. One of the most widely studied examples of signal amplification for sensing applications is based on fluorescent conjugated polymers. Signal amplification in that case is made possible by delocalization of excitation energy within linearly conjugated chromophores that contain a large number of receptors. Instead of activating multiple independent fluorescent sensors with as many photons to detect a small fraction of binding events, which cause a small signal change, conjugated polymer sensors make it possible to detect a fewer binding events by having a large number of receptors sharing the excitation in a super-chromophore chain. However, the maximum quantum yield available by this amplification strategy is one event per photon, i.e., Φ≤1.0. By contrast, quantum chains have the potential for more then one chemical event per photon and could be used to develop chemical amplification with a gain, that is, Φ >>1.0. Quantum chain reactions rely on adiabatic reactions that generate a product in the excited state followed by energy transfer to generate a new excited state reactant, which is able to continue the chain. This presentation will include an introduction to quantum chains processes and analyze several examples that illustrate their remarkable potential for materials applications in the solid state.
The University of Waterloo acknowledges that much of our work takes place on the traditional territory of the Neutral, Anishinaabeg and Haudenosaunee peoples. Our main campus is situated on the Haldimand Tract, the land granted to the Six Nations that includes six miles on each side of the Grand River. Our active work toward reconciliation takes place across our campuses through research, learning, teaching, and community building, and is centralized within our Indigenous Initiatives Office.