In this Minority Research Initiation project in the Chemistry Division, Edwin Carrasquillo M. of the University of Houston will study quantum state-resolved collision dynamics involving polyatomic molecules which contain chemically significant amounts of vibrational energy. The combination of direct excitation using a single-photon overtone vibration to prepare a molecule in a specific quantum state, together with laser-induced fluorescence as a spectroscopic probe, allows the temporal evolution of a hot molecule to be monitored. Various hydrogen-containing molecules, such as HCN, DCN, HCP, and propynal, will be studied in order to extract relaxation mechanisms and identify general trends. %%% Studies of energy transfer involving very high vibrational levels are important for understanding many chemical processes, including reactions. Knowing how the internal energy of a reactant affects the reaction path or how the excess internal energy of a product is redistributed as it equilibrates with its surroundings can help in efforts to control the course of a chemical reaction. This project aims at examining the behavior of molecules with large but very precisely determined amounts of energy present in the vibrations of individual chemical bonds.