title: [XIm][FeI(CO)3(SnI3)2] (XIm: EMIm, EHIm, PMIm) containing a barbell-shaped FeSn2-carbonyl complex.
abstract: By reacting Fe(CO)(5) and SnI(4) in the ionic liquids [XIm][NTf(2)] (XIm: 1-ethyl-3-methylimidazolium/EMIm, 1-ethyl-imidazolium/EHIm, 1-propyl-3-methylimidazolium/PMIm; NTf(2): bistrifluoridomethansulfonimide), the compounds [XIm][FeI(CO)(3)(SnI(3))(2)] are obtained as transparent, dark red crystals. According to single-crystal structure analysis, the title compounds crystallize monoclinically and contain the anionic carbonyl complex [FeI(CO)(3)(SnI(3))(2)](-) as well as [EMIm](+), [EHIm](+) or [PMIm](+) cations. The anionic carbonyl is composed of a Sn-Fe-Sn barbell-shaped building unit with Fe-Sn distances of 252.0(1) pm. Herein, tin is coordinated distorted tetrahedrally by iodine; iron is coordinated pseudo-octahedrally by three carbonyl ligands, one iodine atom and two tin atoms. Bonding situation and valence state are investigated in detail for [EMIm][FeI(CO)(3)(SnI(3))(2)] based on bond-lengths considerations, infrared spectroscopy, Mössbauer spectroscopy, density functional theory and DFT-based Mulliken population analysis. Hence, the formal oxidation state of the metal atoms can be concluded to Fe(±0) and Sn(3+).
authors: Institut für Anorganische Chemie, Karlsruhe Institute of Technology (KIT), Engesserstrasse 15, D-76131 Karlsruhe, Germany.
authors: Silke
authors: S
authors: Wolf
authors: Florian
authors: F
authors: Winter
authors: Rainer
authors: R
authors: Pöttgen
authors: Nils
authors: N
authors: Middendorf
authors: Wim
authors: W
authors: Klopper
authors: Claus
authors: C
authors: Feldmann