Haber-Weiss process

There is no doubt that transition metal complexes are able to catalyze the oxygenation and oxidation of organic substrates which otherwise would only react slowly or not at all with molecular oxygen. In most of these cases, however, the reaction is inhibited by free radical scavengers and shows an initial induction period, which is undoubtedly due to an initiating step typified by the Haber-Weiss process (eq. 4) (9,15). 

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