PREDICTIVE VALUE OF A MODEL OF THE BRIGGS-RAUSCHER REACTION FITTED TOQUENCHING EXPERIMENTS

We describe a model of the Briggs-Rauscher reaction closely related to those due to Furrow and Noyes and to DeKepper and Epstein. The model has been fitted to 16 experimental basic quenching parameters at a Hop f bifurcation point. The fit is quite good. Predictions of the model a re compared with experiments close to the Hopf bifurcation as well as at several operating points away from it and with experiments under ba tch conditions. The angular frequency of the finite limit cycle oscill ations near the Hopf bifurcation is half the value observed in the exp eriments. The relative phases of the concentration oscillations of O-2 and I- agree reasonably well with the experiments, but the average va lues are 1 or 2 orders of magnitude smaller in the simulations. The mo del demonstrates that it is possible to account for a paradoxical beha vior of perturbation by OH- as compared to that of H+ and that quenchi ng from a finite limit cycle may be impossible to realize. It qualitat ively explains four distinct quenching experiments by dilution. At thr ee separate operation points away from the Hopf bifurcation the model reproduces two observed patterns, namely, one of bistability between a stationary state and a limit cycle and one of mixed mode oscillations , but it fails to reproduce observed burst oscillations at the appropr iate point. The model can reproduce transient batch mode oscillations and other transient behavior, The model of Furrow and Noyes with a mor e recent set of rate constants and a reduced version of it, derived by sensitivity analysis, are also compared with experiments.