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 are modelled as a stochastic birth and death process. The transformation from the hexagonal phase to the (1x1)-phase is described by a GLAUBER dynamics. The stochastic simulation performed for the one-dimensional case shows qualitative agreement with the experimental results. Moreover, equations for the averaged densities are derived, discussed and numerically solved. Our investigation shows that the oscillatory behaviour is generated by stochastic ignitions of fronts and pulses in an excitable and in a bistable regime.