STOCHASTIC DYNAMICS OF CATALYTIC CO OXIDATION ON PT(100)

We investigate the dynamics of the CO oxidation on Pt(100) by means of a master equation approach. Adsorption, diffusion and the reaction ar e modelled as a stochastic birth and death process. The transformation from the hexagonal phase to the (1 x 1)-phase is described by a Glaub er dynamics. The stochastic simulation performed for the one-dimension al case shows qualitative agreement with the experimental results. Mor eover, equations for the averaged densities are derived, discussed and numerically solved. Our investigation shows that the oscillatory beha viour is generated by stochastic ignitions of fronts and pulses in an excitable and in a bistable regime.