Reactivity of Radicals in Crystal Lattices

University Of Cincinnati Main Campus, Cincinnati OH

Investigators

Abstract

With this award, the Chemical Structure, Dynamics & Mechanism Program is supporting Professor Anna Gudmundsdottir at the University of Cincinnati to investigate the solid-state photochemistry and photophysics of naphthoquinones and vinyl azides, using a combination of laser flash photolysis and x-ray crystallography. The goal of this research is to elucidate solid-state reaction mechanisms and to explain how a crystal lattice structure can affect reactivity. Professor Gudmundsdottir will integrate the research components of this project with an educational program designed to attract both high school and undergraduate students, with a focus on enhancing participation of students from groups that are underrepresented in science. Students will be provided with an opportunity to participate in research and educational activities that focus on professional development. The proposed research and the developmental teaching will lead to enhanced infrastructure within the Chemistry Department at the University of Cincinnati and serve as an outreach program for other schools in the region. This research will investigate the solid-state photoreactivity of naphthoquinones and vinyl azides by identifying their photoproducts and acquiring their X-ray structures. Laser flash photolysis will be used to characterize the transient excited states and radicals which are formed in the crystals and to determine the kinetics for their formation and decay. Collectively, these data will make it possible to elucidate detailed solid-state reaction mechanisms and to explain how the crystal lattice affects behavior of transient species and selection of the reaction products. Mechanistic studies will be supported by theoretical calculations. The planed studies, will lead to new knowledge in the field of photochemistry, reactive intermediates and solid-state chemistry. The proposed research will also contribute toward the design of crystal lattices for selective carbon-carbon and carbon-nitrogen bond formation from radicals, with a goal of using crystals as a matrix for solvent-free synthesis. Simultaneously, this research will contribute to the design of photoresponsive devices, such as solar cells and light emitting diodes.