Dr. Felker plans to carry out a program of research which falls into three areas, all involving time-integrated and picosecond time-resolved spectroscopy on jet-cooled species. In the first, picosecond spectroscopy will be applied to the study of vibrational energy flow in the electronic ground-state manifolds of molecules. His second major area of interest is the application of the (recently observed) rotational coherence phenomenon to high-resolution molecular spectroscopy and to studies of the rotational state-changing collisions of large species. In the spectroscopic studies, rotational coherence effects will be used to obtain sub-Doppler, megahertz resolution measurements of the rotational constants of molecular complexes and clusters, with the aim of elucidating the structures of the species. His third area of interest is the spectroscopy and dynamics of jet-cooled, isolated transition-metal coordination complex ions. This work is important because it involves looking at energy flow within molecules. Questions such as how rapidly vibrational energy once deposited in a specific mode is redistributed in a molecule and just where it ends up are of fundamental importance to understanding chemical reactivity.