Metal Complexes of Donor-Bridge Acceptor Biradical Ligands: Testing Models for Electron Transport

North Carolina State University, Raleigh NC

Investigators

Abstract

In this project funded by the Chemical Structure, Dynamic & Mechanism B Program of the Chemistry Division, Professor David A. Shultz of the Department of Chemistry at North Carolina State University is studying detailed relationships between a molecule's structure and its capacity to transport electrons in molecule-based electronic devices. The goal of this research is to develop lucid connections between a molecule's shape/structure and its ability to transport electrons in an electrical circuit. The results could have application in the next generation of molecular electronics and "spintronics" (electron spin-based electronics). The project requires detailed studies of molecular synthesis, structure determination, spectroscopy, theory, and is well-suited to the education of scientists. The Shultz group has extensive experience in training scientists (including undergraduates and those from underrepresented groups) who go on to careers in academia, government laboratories, industry, and entrepreneurship. Outreach activities include hosting and training undergraduate summer researchers from Shaw University, a local Historically Black University. Electron donor-acceptor interactions control electron transfer and transport at the molecular level. They are crucial, foundational elements in biological and artificial electron transfer and photosynthesis, solar energy conversion and molecular electronics/spintronics (electron spin-based electronics). The research continues the efforts toward an elucidation of electronic coupling in Donor-Bridge-Acceptor systems in which the donor fragment is a metal-semiquinone and the acceptor is a nitronylnitroxide radical, and the magnetic electron spin-spin exchange coupling between the two is directly proportional to the square of the Donor-Acceptor electronic coupling. The focus is on elucidating factors affecting molecular current rectification, and molecular design elements that might serve as tunnel junctions in molecular current rectifiers (e.g., cross-conjugation and non-alternate hydrocarbons). 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.