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Updated: Jun 23, 2026

Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
Mössbauer, NMR, geometric, and electronic properties in S = 3/2 iron porphyrins
1Department of Chemistry, University of Southern Mississippi, 118 College Drive #5043, Hattiesburg, Mississippi 39406, USA.
Abstract:
Iron porphyrins with the intermediate spin S = 3/2 or admixed with S = 5/2 or 1/2 are models for a number of heme protein systems, including cytochromes c'. The (57)Fe Mossbauer quadrupole splittings and (1)H and (13)C NMR chemical shifts have been found to be useful probes of their electronic states. We present the results of the first successful quantum chemical calculations of the Mössbauer and NMR properties in various S = 3/2 iron porphyrin complexes, covering four-, five-, and six-coordinate states and three commonly seen porphyrin conformations: planar, ruffled, and saddled. Several interesting correlations among these useful experimental spectroscopic probes and geometric and electronic properties were discovered. These results should facilitate future investigations of related heme proteins and model systems.
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