Transition between Fronts and Spiral Waves in a Bistable Surface Reaction

Abstract

The transition between wave fronts and spiral waves in the CO oxidation on a Pt(110) surface has been investigated by means of photoemission electron microscopy and treated theoretically by simulations with a reaction-diffusion model under bistable conditions. Periodic external forcing of spirals near the transition to front behavior led to a complex pattern best characterized as a pulsating spiral-front hybrid, thus confirming the bistable nature of the underlying reaction kinetics.