XAFS STUDIES OF HIGH-VALENT PORPHYRINATO MANGANESE COMPLEXES WITH OZONE

We produce strong evidence of the interaction of ozone with a series o f Manganese (III) porphyrinato complexes to form a well defined reacti ve intermediate. In the latter species, the Manganese atom which is fo rmally in a tetravalent (IV) state, is (at least) hexacoordinated with the metal unambiguously lying in the basal plane of the four pyrrolic nitrogens of the porphyrin macrocycle. Substitution of Bromine or Chl orine axial ligands by ozonids is most likely to happen. This conclusi on is also supported by XANES and EXAFS spectra recorded at the Chlori ne K-edge which suggest that ozone may even form with chlorine a compl ex anion.