Abstract
The precursors of the metal-complexed paramagnetic intermediates generated in the course of redox reactions of hydrogen peroxide with metal ions have been studied by esr spectroscopy using in situ radiolysis. Thus the necessity of adding H2O2 and the interference of the resulting peroxy complexes were avoided. No complexed species were formed from the free metal ion in the absence of HO2 radicals. However, when peroxy-metal complexes were present in the system both ·OH and HȮ2 gave rise to the same secondary species. The results indicate that the complexed radicals are formed through direct addition of HȮ2 radical to the metal ion as well as via one-electron oxidation of peroxy-metal complexes by ·OH and HȮ2. These results support the formulation of the species produced in all cases as M-O-O ·. It was found also that ZrIV and HfIV in each case react with HȮ2 to yield two different paramagnetic transients similar to those obtained from TiIV.
Original language | English |
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Pages (from-to) | 2207-2213 |
Number of pages | 7 |
Journal | Journal of Physical Chemistry |
Volume | 76 |
Issue number | 16 |
DOIs | |
State | Published - 1972 |
Externally published | Yes |