PHOTODECOMPOSITION DYNAMICS OF MO(CO)6 SI(111)7X7 - CO INTERNAL STATEAND TRANSLATIONAL ENERGY-DISTRIBUTIONS/

The rotational state and translational energy distributions of CO phot odesorption products resulting from the 266 nm photolysis Of Mo (CO)6 adsorbed on Si(111) 7 X 7 with coverages in the multilayer regime are reported. State-resolved measurements show two desorption components w ith highly disparate energy dispositions. Results for different surfac e temperatures indicate that the energy content in one component reach es quasi-equilibration with the surface temperature, which is attribut ed to collisional relaxation of nascent photodecomposition products wi thin the adlayer. The other component exhibits disparate rotational an d translational ''temperatures'' that are significantly greater than, and independent of, the surface temperature. These nascent photodecomp osition products are influenced by both energy quenching effects and d ynamical constraints imposed by the existence of the adlayer.