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Abstract

In oscillatory surface reactions on single crystal surfaces the partial pressure variations that accompany the oscillations in the reaction rate represent a global interaction between the local oscillators. The NO+CO reaction on Pt(100) exhibits both synchronized and unsynchronized oscillatory behavior depending on the substrate phase. Unsynchronized oscillations occur on the 1×1 phase but on the hex phase one finds synchronized oscillatory behavior. The mechanism leading to synchronization in the oscillations on Pt(100)‐hex can be traced back to a critical dependence of the 1×1⇄hex phase transition on the partial pressures of NO and CO. At both ends of the temperature window for rate oscillations one finds well‐defined transitions to a stationary reaction rate. These bifurcations are discussed in terms of a transition from synchronized to unsynchronized behavior. In particular, the occurrence of deterministic chaos in connection with a Feigenbaum scenario is interpreted as being due to such a transition.