title: A trans-1,2 End-On Disulfide-Bridged Iron-Tetracarbene Dimer and Its Electronic Structure.
abstract: A disulfide-bridged diiron complex with [Fe-S-S-Fe] core, which represents an isomer of the common biological [2Fe-2S] ferredoxin-type clusters, was synthesized using strongly σ-donating macrocyclic tetracarbene capping ligands. Though the complex is quite labile in solution, single crystals were obtained, and the structure was elucidated by X-ray diffraction. The electron-rich iron-sulfur core is found to show rather unusual magnetic and electronic properties. Experimental data and density functional theory studies indicate extremely strong antiferromagnetic coupling (-J > 800 cm(-1)) between two low-spin iron(III) ions via the S2(2-) bridge, and the intense near-IR absorption characteristic for the [Fe-S-S-Fe] core was assigned to a S → Fe ligand-to-metal charge transfer transition.
authors.affiliation: Institut für Anorganische Chemie, Georg-August-Universität Göttingen , Tammannstraße 4, 37077 Göttingen, Germany.
authors.forename: Steffen
authors.initials: S
authors.lastname: Meyer
authors.affiliation: Max Planck Institute for Chemical Energy Conversion , Stiftstraße 34-36, 45470 Mülheim an der Ruhr, Germany.
authors.forename: Oliver
authors.initials: O
authors.lastname: Krahe
authors.affiliation: Institut für Anorganische Chemie, Georg-August-Universität Göttingen , Tammannstraße 4, 37077 Göttingen, Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Kupper
authors.affiliation: Institut für Anorganische Chemie, Georg-August-Universität Göttingen , Tammannstraße 4, 37077 Göttingen, Germany.
authors.forename: Iris
authors.initials: I
authors.lastname: Klawitter
authors.affiliation: Institut für Anorganische Chemie, Georg-August-Universität Göttingen , Tammannstraße 4, 37077 Göttingen, Germany.
authors.forename: Serhiy
authors.initials: S
authors.lastname: Demeshko
authors.affiliation: Max Planck Institute for Chemical Energy Conversion , Stiftstraße 34-36, 45470 Mülheim an der Ruhr, Germany.
authors.forename: Eckhard
authors.initials: E
authors.lastname: Bill
authors.affiliation: Max Planck Institute for Chemical Energy Conversion , Stiftstraße 34-36, 45470 Mülheim an der Ruhr, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Neese
authors.affiliation: Institut für Anorganische Chemie, Georg-August-Universität Göttingen , Tammannstraße 4, 37077 Göttingen, Germany.
authors.forename: Franc
authors.initials: F
authors.lastname: Meyer
mesh_terms: D018360:Crystallography, X-Ray; D019281:Dimerization; D004220:Disulfides / Q000737:chemistry*; D004583:Electrons; D005290:Ferric Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D011789:Quantum Theory
chemical_list: D004220:Disulfides; D005290:Ferric Compounds