Molecular and electronic structure of a mixed-valent class II, dinuclear complex containing a linear [Fe^II–O–Fe^III]³⁺ core

Abstract

One-electron reduction of [{LFe^III(Ph₂acac)}₂(µ-O)] [BPh₄]₂ 1[BPh₄]₂ (L = 1,4,7-trimethyl-1,4,7-triazacyclononane, Ph₂acac^- = 1,3-diphenylpropane-1,3-dionate) in CH₂Cl₂–toluene by 1 equiv. of cobaltocene produces the mixed-valent complex [{LFe(Ph₂acac)}₂(µ-O)][BPh₄ ]·C₆H₅Me 2[BPh₄]· C₆H₅Me which is characterized by X-ray crystallography; 2 has an S = ½ ground state (antiferromagnetically coupled high-spin Fe^III and high-spin Fe^II with J = -65 cm^-1) and exhibits class II behaviour according to the Robin and Day classification.

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