Precursor-mediated chemisorption for activated systems

In addition to molecular beam experiments, bulb experiments of methane on Ir(l 1 0)/Ir(l 1 1) were conducted in an attempt to determine the degree of contributions from the trapping-mediated and 

Surface Temperature, Ts (K) S0 (Bulb Expt.) So (Calc.) % Trapping Mediated % Direct 

Values ofS0,t determined experimentally from bulb experiments and those determined from calculations using molecular beam data atrg = 300 K. Also included, are calculated contributions toSG from the trapping mediated and direct mechanisms for methane dissociation on Ir(l 1 0)-(l x 2). 

Excellent agreement was obtained between the calculated, S 01 values and those determined experimentally from the bulb gas experiments. Table 2 shows these, S 01 values and the calculated fractions of So,t due to the trapping and direct mechanisms. 

Shown in Fig. 18 is a plot of S0 vs. incident translational energy (Et) for Ts = 400 K and various nozzle temperatures ranging from 300 to 800 K. 

---