Substrate effects on the fractal kinetics of a simple surface reaction

The reversible monomer-monomer model occurring without diffusion on irregul ar substrates (probabilistic supports and Sierpinski carpets) is investigat ed by means of Monte Carlo simulations. The strong influence of the catalys t surface structure on the kinetics of the reaction and its fractal like fe atures such as noninteger reaction rate orders is investigated for steady-s tate regimes controlled by the reaction. We succeed in separating the depen dence of the reaction rate orders on adsorbate cluster parameters from that on bare surface geometry specifics. The inactivity ratio rho appears to be the relevant parameter to characterize the bare surface structure effects on the Langmuir-Hinshelwood reaction kinetics. (C) 2001 American Institute of Physics.