Under this NSF Young Investigator Award Professor Seung Koo Shin will examine photoinitiated reactions in ion-molecule complexes near the transition state. Ionic reaction intermediates weakly held by charge-induced dipole interactions are isolated in an ion trap or are mass-selected with an ion reflector. State-selective laser spectroscopic studies provide details of structural and dynamic information about ion-molecule complex mediated chemical processes such as SN2, charge-transfer, and oriented orbital reactions. %%% With the experimental techniques available to him, Shin will be able to examine on a microscopic level what happens when one molecule, sometimes an electrically charged particle called an ion, reacts with a different neutral molecule. The weak molecular associations which are formed are called complexes. The study of these complexes gives information about how reactions occur, and what products result under given starting conditions. These studies have broad application, especially to atmospheric processes, including those involved in the formation of smog an the destruction of greenhouse gases.
