Herein we present the first Mn-K edge EXAFS spectra recorded for manganese(III)porphyrin catalysts containing [Mn{T(4-N-MePy)P}(L)(n)](5+) (where L =oxygenated or nitrogenated axial ligands, n =1 or 2) grafted onto modified silica-surfaces with propylimidazole, IPG (3), sulfonatophenyl, SiSO3_ (4), and both, SiSO(3)(_)IPG (5), where T(4-N-MePy)P is the ligand 5,10,15,20-tetra(4-N-methylpyridyl)porphyrinate. From the data analysis and the refinement results, we have obtained the following structural information concerning to the coordination environment around the Mn(III) ion: four Mn-N at 2.00 angstrom and two Mn-N/O-axial at 2.26 angstrom for 3; four Mn-N at 2.03 angstrom and two Mn-O-axial at 2.27 angstrom for 4, and four Mn-N at 2.02 angstrom and two Mn-N/O-axial at 2.28 angstrom for 5. Correlations of EXAFS data with UV-vis spectra pattern and other properties such as colors of the materials allowed distinguishing between materials 3, 4 and 5. Materials 4 and 5 belong to the same category, which involves ionic complex-support interaction. Furthermore, there are evidences for the coordination of the imidazolic ligand to the manganese(III) ion in 3 and 5 from qualitative analysis of XANES data. In the case of the catalyst 5, bearing both sulfonate and imidazole as functional groups, we have suggested that the nature of the [Mn {T(4-N-MePy)P}(L)(n)](5+)-support interaction is predominantly of ionic character, even though the existence of Mn-imidazole bonds can be detected. (c) 2005 Elsevier B.V. All rights reserved.