A Coordination Chemistry Approach to the Synthesis of Single-Molecule Magnets

With support from the Chemical Structure, Dynamics & Mechanisms B (CSDM-B) Program of the Chemistry Division, Professor Jeffrey R. Long of the Department of Chemistry at the University of California, Berkeley, is designing and synthesizing new single-molecule magnets. Upon removal of an applied magnetic field, these species display signatures of magnetic memory, a property long thought to arise exclusively from long-range magnetic order in bulk permanent magnet materials. However, the observation of such behavior in individual nanoscopic molecules is remarkable and may lead to transformative advances in areas such as high-density data processing, quantum information science, and quantum sensing. This project lies at the interface of synthetic molecular chemistry and physics and is therefore ideally suited for interdisciplinary young scientists with broad interests and for promoting the inclusion of students from underrepresented backgrounds. Finally, an outreach program will seek to educate Bay Area K–12 students on the role and wonder of magnetic molecules in society. This research will employ fundamental molecular design principles to newly synthesize single-molecule magnets, aiming for systems with high operating temperatures. The project will test the central hypothesis that coordination chemistry can enable the synthesis of molecules with tailored electronic structures, thereby giving rise to single-molecule magnets with unprecedented operating temperatures. More specifically, this proposal focuses on the design and synthesis of new lanthanide- and transition metal-based molecules with (i) maximal axial crystal-field anisotropy to give high relaxation barriers and (ii) strong magnetic exchange interactions to mitigate deleterious quantum tunneling. This project will expand our knowledge of how to manipulate a wide range of magnetic properties in molecules, including single-ion magnetic anisotropy, magnetic coercivity, and magnetic coupling interactions. The fundamental knowledge generated from this project may lead to advances in myriad technological areas–including quantum information science, ultra-hard magnetism, and biomedical imaging. 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.