Coverage dependence of the kinetics for H 2 desorption from Rh ( 111 )
نویسنده
چکیده
Coverage-dependent sticking probabilities and second-order rate constants for recombinative desorption of hydrogen from Rh( 111 ) have been measured using molecular beam relaxation spectroscopy (MBRS) and time-resolved specular helium scattering. The sticking probability follows second-order Langmuir coverage dependence, with So equal to 0.01 ___ 0.005. Under isothermal and nearly isosteric conditions over the coverage range 0.2-0.7 ML, the second-order rate constant for desorption is essentially independent of hydrogen coverage, in contrast to kinetic parameters determined from thermal desorption spectra.
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