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Updated: Jun 28, 2026

Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
A mixed-valence octanuclear iron-oxo pyrazolate: assessment of electronic delocalization by structural and
Indranil Chakraborty1, Peter Baran, Yiannis Sanakis
1Department of Chemistry and the Institute of Functional Nanomaterials, University of Puerto Rico, San Juan, PR 00931-3346.
Abstract:
A formally Fe(III)(7)Fe(II) complex, containing an inner Fe(4)O(4)-cubane and four peripheral Fe centers, is derived from the one-electron reduction of its Fe(III)(8) precursor. Spectroscopic analysis of the former reveals that the redox activity of this Fe(8) system is confined within its cubane core. The resulting (Fe(4)O(4))(3+)-cubane, which is valence-delocalized in the NMR, Mössbauer, and IR spectroscopy time scales but valence-trapped in the X-ray photoelectron spectroscopy (XPS) time scale, is better described as a Robin-Day class-II system by the analysis of its near-infrared (NIR) intervalence charge transfer (IVCT) band profile.
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