Modeling the Behavior of Pyruvic Acid at the Air-Water Interface

Presenter(s): Benjamin Muller − Chemistry

Faculty Mentor(s): Brittany Gordon, Dr. Geraldine Richmond

Poster 16

Research Area: Physical Chemistry

Studying the air-water interface provides valuable knowledge on important environmental systems like atmospheric aqueous secondary organic aerosol (aqSOA). Many small, aqueous organics that are known to contribute to aqSOA formation can further react in the air-water phase to form hydrated molecules. Since the atmosphere is a complex and variable place with many phases and interfacial regions it is difficult isolating this hydration process within particular organic systems. Modeling this behavior of hydrated organics at this interface is largely unknown. Pyruvic acid (PA) is an abundant atmospheric ketone found in aqSOA. Our research objective is to examine PA at the planar air-water interface using vibrational sum- frequency spectroscopy (VSFS). Sum frequency is a technique that shines visible and infrared light where air and water meet to understand molecular populations and behaviors of ordered molecules. Surface tensiometry measurements from the Wilhelmy plate will reveal the time dependency between PA and this complex system. Both techniques will help characterize how depth, conformational populations and orientation changes between the bulk, surface, and subsurface. This research will act as a platform to easily branch out to other systems of organics for future air-water interfacial studies.