Subpicosecond Spectroscopy Gives New Data on Reaction Dynamics

Abstract

Many chemical processes take place with breathtaking rapidity, on time scales of trillionths or even quadrillionths of a second. Spectroscopists trying to understand the details of such fundamental processes as the breaking of a chemical bond or intramolecular energy redistribution have long been confronted with the simple fact that their experimental techniques could not keep pace with many of the events being studied. One response has been the design of ingenious experiments that allow researchers to use data on the outcome of such an event to say something about the details of the event itself. Such so-called indirect determinations have provided a wealth of information on relative rates of reactions and energy redistribution. However, such extrapolations require a variety of assumptions that may or may not turn out to be accurate. Moreover, such experiments do not permit direct viewing of the transition state, the state between reactants and products. Another response has been development and ...