Trisha Bhagde

In Penn’s Master of Chemical Sciences program, Trisha Bhagde’s physical chemistry research is concerned not only with atoms but with the atmosphere. “I have always wanted to understand the different reactions that lead to the atmospheric events that we see around us,” she says. “Global warming is a major issue now, and at this point, the environment is one of the most relevant things to study in order to understand where we’re going wrong and how we can fix it.”

Now working in a Penn lab dedicated to studying Criegee intermediates—a class of molecules which play a key role in oxidation reactions in the atmosphere—Trisha is able to combine her interests in physical and atmospheric chemistry as she learns lab techniques and conducts her capstone research. “What I do in the lab is mostly spectroscopy. There a lot of molecules in the atmosphere, and we need a kind of fingerprint to identify them,” she explains. Using the depletion method coupled with time-of-flight mass spectrometry, Trisha is characterizing a four-carbon Criegee intermediate by seeing how it absorbs different wavelengths of light. Because the molecule of interest is studied in the gas phase, Trisha and her fellow researchers characterize them under high vacuum conditions. “Our experiments are conducted in an isolated environment to accurately record the spectrum of the Criegee intermediate. High vacuum conditions also ensure low density as observed in the upper layers of the atmosphere, where the molecules are far apart from each other,” she says. “This method is simple and yet sophisticated, and gives a lot of information about the molecule in question.” Trisha complemented her lab and capstone research by taking classes in quantum chemistry, chemical dynamics, molecular spectroscopy and statistical mechanics in the chemistry department, and optics and astrophysical radiation from the physics department.

“I’ve always wanted a PhD, but I never had long-term lab exposure,” Trisha reflects. “While I do my capstone, I am in the lab five days a week, so it’s giving me an idea of what’s in store for a PhD.” She looks forward to pursuing physical chemistry in her future studies and contributing to the growing body of research on atmospheric change. “I’m just working on one molecule, but this could be a fingerprint for future atmospheric chemists to refer to,” she says of her capstone research. “It’s one step closer to understanding what’s going on out there.”