Perturbation of bromate oscillators Pt. 1

Reacting BZ systems of different catalysts [Ce3+, Mn2+, Fe(phen)32+, Ru(dipy)32+] have been perturbed by 60Co γ irradiation. At high bromate concentrations (between 0.15 and 0.1 molxdm-3) γ irradiation has no effect on the chemical oscillation irrespectively of the catalyst used. At lower bromate concentrations the oscillation is either quenched or considerably decreased in frequency in the case of cerium(III) or manganese(II). BZ systems with Fe(phen)32+ or Ru(dipy)32+ as a catalyst are not affected by γ irradiation. The major role of H atoms - produced in the radiolysis of water - is discussed, and the claim of other authors that the inhibitory effect can be attributed to bromide ions formed in the BrMA+H reaction is criticized. (author)