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Isolation and characterization of a high-spin mixed-valent iron dinitrogen complex.

ABSTRACT: We report a rare example of a mixed-valence iron compound with an FeNNFe core, which gives insight into the structural, spectroscopic, and magnetic influences of single-electron reductions and oxidations. In the new compound, the odd electron is localized as judged from Mössbauer spectra at 80 K and infrared spectra at room temperature, and the backbonding into the N2 unit is intermediate between diiron(i) and diiron(0) congeners. Magnetic susceptibility and relaxation studies on the series of FeNNFe compounds show significant magnetic anisotropy, but through-barrier pathways enable fairly rapid magnetic relaxation.

SUBMITTER: McWilliams SF

PROVIDER: S-EPMC6258315 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Isolation and characterization of a high-spin mixed-valent iron dinitrogen complex.

McWilliams Sean F SF Bunting Philip C PC Kathiresan Venkatesan V Mercado Brandon Q BQ Hoffman Brian M BM Long Jeffrey R JR Holland Patrick L PL

Chemical communications (Cambridge, England) 20181101 95

We report a rare example of a mixed-valence iron compound with an FeNNFe core, which gives insight into the structural, spectroscopic, and magnetic influences of single-electron reductions and oxidations. In the new compound, the odd electron is localized as judged from Mössbauer spectra at 80 K and infrared spectra at room temperature, and the backbonding into the N2 unit is intermediate between diiron(i) and diiron(0) congeners. Magnetic susceptibility and relaxation studies on the series of F ...[more]

PMID: 30403226

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