Structural and Spectroscopic Characterization of (μ-Hydroxo or μ-Oxo)(μ-peroxo)diiron(III) Complexes:  Models for Peroxo Intermediates of Non-Heme Diiron Proteins

(μ-Hydroxo or oxo)(μ-1,2-peroxo)diiron(III) complexes having a tetradentate tripodal ligand (L) containing a carboxylate sidearm [Fe2(μ-OH or μ-O)(μ-O2)(L)2]n+ were synthesized as models for peroxo-intermediates of non-heme diiron proteins and characterized by various physicochemical measurements including X-ray analysis, which provide fundamental structural and spectroscopic insights into the peroxodiiron(III) complexes.