Sum Frequency Generation Spectroscopy
Sum frequency generation (SFG) is a type of vibrational spectroscopy in which infrared and visible laser pulses are overlapped in time and space at an interface. Unlike most spectroscopic techniques, SFG provides information exclusively about the chemistry of interfaces, which allows us to study the surfaces of SSA particles, without contributions from the bulk. Probing the surface through C-H bond vibrations allows for an understanding of the surface orientation of organic molecules, while probing O-H vibrations provides information about the structure of water at the gas-liquid interface and its interactions with solutes and thin organic films.
Gas-Liquid Molecular Beam Scattering
In order to understand the fundamental physical chemistry of reactions at complex environmental interfaces, the Nathanson Research Group will use a gas-liquid molecular beam scattering technique. This apparatus directs a beam of gaseous reagent molecules at a liquid surface, inducing a chemical reaction at the gas-liquid interface. A mass spectrometer is used to determine the identity and quantity of the product gases. These studies will complement heterogeneous chemistry studies performed by the Bertram (experimental) and Paesani (computational) research groups.