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Mossbauer, NMR, geometric, and electronic properties in S = 3/2 iron porphyrins.

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.

SUBMITTER: Ling Y

PROVIDER: S-EPMC2730173 | biostudies-literature | 2009 May

REPOSITORIES: biostudies-literature

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Mössbauer, NMR, geometric, and electronic properties in S = 3/2 iron porphyrins.

Ling Yan Y Zhang Yong Y

Journal of the American Chemical Society 20090501 18

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-coordina ...[more]

PMID: 19415933

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Mossbauer, NMR, geometric, and electronic properties in S = 3/2 iron porphyrins.

Publications

Mössbauer, NMR, geometric, and electronic properties in S = 3/2 iron porphyrins.

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