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Identification of a Two-Coordinate Iron(I)-Oxalate Complex.

ABSTRACT: Exotic oxidation states of the first-row transition metals have recently attracted much interest. In order to investigate the oxidation states of a series of iron-oxalate complexes, an aqueous solution of iron(III) nitrate and oxalic acid was studied by infrared free liquid matrix-assisted laser desorption/ionization as well as ionspray mass spectrometry. Here, we show that iron is not only detected in its common oxidation states +II and +III, but also in its unusual oxidation state +I, detectable in both positive-ion and in negative-ion modes, respectively. Vibrational spectra of the gas phase anionic iron oxalate complexes [Fe^III (C₂ O₄ )₂ ]^- , [Fe^II (C₂ O₄ )CO₂ ]^- , and [Fe^I (C₂ O₄ )]^- were measured by means of infrared photodissociation spectroscopy and their structures were assigned by comparison to anharmonic vibrational spectra based on second-order perturbation theory.

SUBMITTER: Mayer M

PROVIDER: S-EPMC9303725 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature

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Identification of a Two-Coordinate Iron(I)-Oxalate Complex.

Mayer Martin M Vankova Nina N Stolz Ferdinand F Abel Bernd B Heine Thomas T Asmis Knut R KR

Angewandte Chemie (International ed. in English) 20220224 16

Exotic oxidation states of the first-row transition metals have recently attracted much interest. In order to investigate the oxidation states of a series of iron-oxalate complexes, an aqueous solution of iron(III) nitrate and oxalic acid was studied by infrared free liquid matrix-assisted laser desorption/ionization as well as ionspray mass spectrometry. Here, we show that iron is not only detected in its common oxidation states +II and +III, but also in its unusual oxidation state +I, detectab ...[more]

PMID: 35088489

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