Project Grant 2301298

The Trustees of the University of Pennsylvania (Penn) received a $605,000 project grant award from the National Science Foundation (NSF) under the Mathematical and Physical Sciences program (CFDA 47.049) to study the unimolecular decay dynamics of carbonyl oxide intermediates generated through alkene ozonolysis. Professor Marsha Lester of Penn and her team will use molecular spectroscopic and theoretical methods to investigate novel rearrangement mechanisms of these reaction intermediates that lead to different atmospheric chemistry products. Specifically, the team will combine infrared laser activation of carbonyl oxides with time-resolved detection of hydroxyl radical products to measure unimolecular decay rates and transition state barriers leading to products. Theoretical modeling will examine 1,3-ring closure mechanisms in carbonyl oxide decay. Additional studies will characterize alternative products from intra-fragment roaming reactions. This work could enhance understanding of hydroxyl radical generation and other products that impact new particle formation in the atmosphere. The three-year project was awarded on May 15, 2023.