This project is in the general area of analytical and surface chemistry and in the subfield of gas-surface reaction dynamics. The research program will investigate the forces between a diatomic molecule and a surface when the molecule is crossing an activation barrier prior to dissociative chemisorption or associative desorption. The anisotropy of the reactive gas-surface potential will be probed as a function of molecular orientation geometry using multiphoton laser ionization spectroscopy to detect the specific states of the products of activated associative recombination. Angle-selected, velocity-selected, polarization spectroscopy will be employed to detect specific chemical events. The results of these experimental studies will provide detailed new insights into how chemical reactions occur on surfaces. In addition they will enable precise testing of theoretical methods of modeling the interaction of molecules with surfaces. Development of reliable methods for constructing potential energy surfaces will in turn facilitate modeling of surface chemical reactions.
