Please join Yale Chemistry for a Junior Faculty Search Seminar in Physical Chemistry with Alexandra Deal, Postdoctoral Scholar in Energy Sciences, from Lawrence Berkeley National Laboratory.
Abstract: Recent evidence for novel chemistry and enhanced reaction rates on water surfaces has implications for environmental and atmospheric chemistry. However, the fundamental causes for these observations are still under investigation, and direct assessment of potential drivers, including increased concentrations, preferential ordering, and reduced solvation, is challenging. In this seminar, I will present Infrared Reflection-Absorption Spectroscopy (IRRAS) studies of static water surfaces and levitated microdroplet studies of reaction kinetics monitored by mass spectrometric (MS) analysis. IRRAS studies are shown to be surface-specific and are used to explore fundamental aspects of the equilibrium water surface including hydrogen bonding and van der Waals interactions between surface-active solutes. Levitated microdroplets are used to study atmospherically relevant non-equilibrium multiphase reactions, and the associated MS analysis provides a high level of kinetic detail which is difficult to obtain from surface-specific methods like IRRAS. Kinetic modeling of the microdroplet reaction kinetics demonstrates that the droplet interface is responsible for most (>99%) of the thiosulfate decay while the droplet bulk is responsible for most (>90%) of the downstream reaction steps leading to products. The findings from these works demonstrate the importance of fundamental studies in piecing together a molecular view of chemistry involving water surfaces.
More information on Alexandra Deal’s research can be found here: Alexandra Deal Publications | Lawrence Berkeley National Lab
Faculty Host: Professor Patrick Vaccaro
This seminar can be viewed online here: Panopto