Angle-resolved measurements of product desorption and reaction dynamics on individual sites

Reviews of recent progress in angle-resolved measurements of desorbing surface reaction products are provided. Their angular and velocity distributions deliver information of the reaction site as well as the reaction mechanism when the molecules are repulsively desorbed. These distribution measurements can yield the symmetry and the orientation of the reaction site and open the dynamic studies of elementary processes on individual sites. This report involves a brief history of dynamic studies of reactive desorption, the principle behind a desorption dynamic approach to reaction sites, and experimental methods. Three principal characteristics for repulsive product desorption are exemplified in reactive CO2 desorption. Site identification and switchover in steady-state catalytic reactions and some results of thermal NO+CO reaction and photo-induced desorption are also described.