| Abstract
| - The mechanism of Lengyel, Li, Kustin, and Epstein (J. Am. Chem. Soc.1996, 118, 3708) for the oscillatorychlorine dioxide−iodide reaction accurately models the reaction in closed and open systems. We investigatedwhether this mechanism minus the single reaction involving chlorine dioxide models the chlorite−iodidereaction equally well. It agrees qualitatively with clock reaction results. As for open system dynamics, themechanism predicts the existence of two steady states and bistability in very nearly the same regions wherethese features are found experimentally in the pH range 2−4. A discrepancy in the range of bistability emergesas pH decreases, and it cannot be remedied by taking into account chlorous acid decomposition. That wewere unable to locate an oscillatory region is of greater significance. Because the chlorite−iodide reaction issensitive to mixing effects, we incorporated a two-parameter model of imperfect mixing but still found nooscillations at physically reasonable parameter values. These discrepancies strongly suggest that to obtainpredictive utility for the chlorite−iodide reaction, revision of the chlorine dioxide−iodide mechanism is required.
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