Molecules (Jul 2024)
[Fe(µ<sub>2</sub>-OH)<sub>6</sub>]<sup>3−</sup> Linked Fe<sub>3</sub>O Triads: Mössbauer Evidence for Trigonal µ<sub>3</sub>-O<sup>2−</sup> or µ<sub>3</sub>-OH<sup>−</sup> Groups in Bridged versus Unbridged Complexes
Abstract
The syntheses, coordination chemistry, and Mössbauer spectroscopy of hepta-iron(III) complexes using derivatised salicylaldoxime ligands from two categories; namely, ‘single-headed’ (H2L) and ‘double-headed’ (H4L) salicylaldoximes are described. All compounds presented here share a [Fe3-µ3-O] core in which the iron(III) ions are µ3-hydroxo-bridged in the complex C1 and µ3-oxo-bridged in C2 and C3. Each compound consists of 2 × [Fe3-µ3-O] triads that are linked via a central [Fe(µ2-OH)6]3− ion. In addition to the charge balance and microanalytical evidence, Mössbauer measurements support the fact that the triads in C1 are µ3-OH bridged and are µ3-O bridged in C2 and C3.
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