Pyeongeun Kim
Assistant Professor of Chemistry
Links
Building laser tools to watch chemistry in tiny droplets
My research explores chemistry in tiny droplets and at interfaces of water. It has recently been discovered that chemical reactions can happen up to a million times faster in droplets < 100 micrometers (thinner than a human hair) than in ordinary solutions. This is because such small droplets have much more surface area relative to their volume than a beaker of solution, so more molecules sit at the interface of water, and interfacial effects dominate over bulk behavior. Recent examples of this accelerated chemistry include ammonia synthesis, the formation of organic bonds, and light-driven reactions, pointing to exciting possibilities for sustainable synthesis and energy applications. Still, why and how these reactions speed up so dramatically remain unresolved.
Studying chemistry in droplets and at interfaces is difficult because most chemistry tools and methods are built for beaker-scale experiments. My approach is to build droplet- and interface-specific tools using laser spectroscopy, allowing us to directly observe what is happening at these these tiny, fleeting environments. Using vibrational Raman spectroscopy, we can track chemical changes occurring inside droplets. Using nonlinear techniques such as second harmonic generation and hyper-Raman spectroscopy, we can go a step further and glimpse the hidden behavior of molecules living at water interfaces.
I teach introductory chemistry and physical chemistry. I like to ask students questions about everyday phenomena to draw out the core chemistry concepts behind them. My goal is to make chemistry relatable and bring a sense of wonder into the classroom, so students are motivated by their own curiosity. I'm also mindful of teaching during a moment of rapid change in learning environments, driven by new AI tools, and I'm interested in understanding how these tools can help learning and where they fall short.
Outside of science, I enjoy water activities (swimming, scuba/free diving, surfing) and music (mixing vinyls and listening to vintage audio) -- when I can tear myself away from watching YouTube or playing video games in bed.
Education
- B.S., Yonsei University
- Ph.D., University of California-San Diego
Current and upcoming courses
Fundamentals of Chemistry with Laboratory
CHEM105
This course is designed for students majoring in the physical and biological sciences as well as those wishing an introduction to modern molecular science. Core principles and applications of chemistry are combined to provide students with a conceptual understanding of chemistry that will help them in both their professional and everyday lives. Topics include principles of nuclear chemistry, atomic and molecular structure, molecular energetics, chemical equilibrium, and chemical kinetics. The laboratory work introduces students to synthesis and structural determination by infrared and other spectroscopic techniques, periodic properties, computational chemistry, statistical analysis, and various quantitative methods of analysis. This course is intended for students who have taken one year of high school chemistry and have a math background equivalent to two years of high school algebra. Students who have AP or IB credit in chemistry, and who elect CHEM 105, forfeit the AP or IB credit.
This course has a required co-requisite laboratory - CHEM 105L.