Physics Department - On-Demand Control of Single-Molecule Chemistry through Vibrational Characterization and Manipulation
Abstract
Chemical processes hinge on the dynamic rearrangement of nuclei within molecules. Controlling these motions with precision has been a long-standing goal in chemistry. My lab focuses on achieving this by manipulating interactions between individual molecules and their nanoscale environment. We engineer the potential energy surface at this scale to control molecular properties such as structure and reactivity. Using vibrational characterization techniques with scanning tunneling microscopy (STM)—including inelastic electron tunneling spectroscopy, action spectroscopy, and our recent advancement in single-molecule infrared absorption spectroscopy—we analyze molecular responses to the variation in the nano-chemical environment by examining their fingerprinting vibrational modes at the sub-molecular scale. By precisely tuning the junction geometry, material, and the interaction between the molecule and other surface entities, we can selectively influence specific bonds, paving the way for bond-selective control in chemistry.
Dr. Shaowei Li is an assistant professor at the University of California, San Diego. He received B.S. in Physics and Mathematics from Nankai University in 2010 and Ph.D. in Physics from the University of California, Irvine in 2017. Before joining UC San Diego, he was a postdoc scholar at Northwestern University and later a Heising-Simons Junior Fellow at UC Berkeley. His research focuses on probing the fundamental properties of low-dimensional systems including single molecules and layered materials with scanning tunneling microscopy and spectroscopy. His group combines scanning tunneling microscopy with optical spectroscopy to explore light-matter interaction at the atomic scale.