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The Energy Dependence of the Ratio of Step and Terrace Reactivity for H2 Dissociation on Stepped Platinum

“…20–22 Cleaning cycles were repeated until no evidence for impurities was found and clear LEED images appeared. From the split pattern of the LEED spots,11, 12 we determined the average terrace widths to be 2.9, 4.0 and 5.9 atoms wide, in agreement with the expectation of 3, 4, and 6 atom‐wide terraces, respectively.…”

“…We have experimentally determined the reaction probability as a function of the kinetic energy of H 2 for three Pt(S) (stepped platinum) surfaces; that is, Pt(211), Pt(533), and Pt(755). From the split pattern of the LEED spots,11, 12 we determine the average terrace widths to be 2.9, 4.0, and 5.9 atoms wide, in agreement with the expectation of 3, 4, and 6 atom‐wide terraces. Figure 1 a shows the reaction probability for Pt(755).…”

Quasiperiodic layers of free-electron metals studied using electron diffraction

“…[23][24][25] Occurence of the periodically alternating single and splitted integer order spots with increasing electron-beam energies ͑i.e., increasing radius of Ewald's sphere͒ has been attributed to an out-of-phase scattering of subsequent terraces and a formula was derived to determine the characteristic electron energies for sharp LEED spots. 24,25 Figure 2 shows the LEED patterns of 1.2 ML Na recorded at various electron-beam energies. LEED spots of fivefold diffraction pattern continuously converge toward the specular spot ͑hidden by the shadow of the electron gun͒ with increasing incident beam energies and we do not observe the splitting of the LEED spots at any electron energy.…”