A trans-1,2 End-On Disulfide-Bridged Iron-Tetracarbene Dimer and Its Electronic Structure

作者：Meyer Steffen; Krahe Oliver; Kupper Claudia; Klawitter Iris; Demeshko Serhiy; Bill Eckhard; Neese Frank; Meyer Franc

来源：Inorganic Chemistry, 2015, 54(20): 9770-9776.

DOI：10.1021/acs.inorgchem.5b01446

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 sigma-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 S-2(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.

• 出版日期2015-10-19