With the joint support of the Macromolecular, Supramolecular and Nanochemistry Program and the Chemical Synthesis Program in the Division of Chemistry, Elisa Tomat and coworkers at the University of Arizona will employ biologically inspired pigments to synthesize novel supramolecular assemblies with highly tunable magnetic and photophysical properties. This project aims to gain a fundamental understanding of the resulting electronic structures and properties to inform future design of supramolecular materials for potential applications such as in light-harvesting devices, photocatalytic systems, and molecular magnets. This project will offer multidisciplinary training to undergraduate and graduate students as well as opportunities for professional growth through university-wide mentoring programs and outreach activities. Dr. Tomat leads the Chemistry Discovery program at the University of Arizona, that provides a framework for college students to discuss scientific concepts with middle-school students, promoting the pursuit science while highlighting the importance of science communication at all levels. This research project will incorporate redox-active biopyrrin ligands in a versatile new class of supramolecular radical assemblies. Biopyrrins, such as tripyrrindiones and dipyrrindiones, feature the scaffolds of biologically occurring heme metabolites as stable platforms for delocalized ligand-based radicals in transition metal complexes. These oligopyrrolic frameworks also present tunable spectroscopic and electrochemical profiles and engage in non-covalent interactions, such as pi-stacking and hydrogen bonding, in solution and in the solid state. Synthetic manipulations of these multi-functional building blocks are expected to allow control of the spin-spin interactions in multi-centered radical and redox-responsive assemblies. Investigations by spectroscopic, electrochemical, crystallographic, and computational methods will provide for a detailed multifaceted characterization of these tunable molecular assemblies and likely enhance fundamental understanding of how to design, build and manipulate supramolecular radical assemblies. 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.