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Updated: Jul 16, 2026

Molten-Salt Synthesis of Complex Metal Oxide Nanoparticles
Published on: October 27, 2018
Crystallographic and spectroscopic characterization of a nonheme Fe(IV)-O complex
Jan-Uwe Rohde1, Jun-Hee In, Mi Hee Lim
1Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota, 207 Pleasant Street SE, Minneapolis, MN 55455, USA.
Abstract:
Following the heme paradigm, it is often proposed that dioxygen activation by nonheme monoiron enzymes involves an iron(IV)=oxo intermediate that is responsible for the substrate oxidation step. Such a transient species has now been obtained from a synthetic complex with a nonheme macrocyclic ligand and characterized spectroscopically. Its high-resolution crystal structure reveals an iron-oxygen bond length of 1.646(3) angstroms, demonstrating that a terminal iron(IV)=oxo unit can exist in a nonporphyrin ligand environment and lending credence to proposed mechanisms of nonheme iron catalysis.
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