Heptacarbonylbis(μ-propane-1,3-dithiolato)triiron(I,II)(2Fe—Fe)

Abstract

Key indicators: single-crystal X-ray study; T = 293 K; mean (C-C) = 0.007 Å; R factor = 0.043; wR factor = 0.056; data-to-parameter ratio = 18.9.The trinuclear title compound, [Fe 3 ]. Both outer Fe I atoms are six-coordinated in a distorted ocahedral coordination geometry defined by the bridging Fe II atom, three carbonyl C atoms and two bridging S atoms. The coordination number of the central Fe II atom is seven and includes bonding to the two outer Fe I atoms, four bridging S atoms and one carbonyl C atom. The resulting coordination polyhedron might be described as a highly distorted monocapped trigonal prism. In the crystal packing, the molecules exhibit a chain-like arrangement parallel to [100] and [001], and the resulting layers are stacked along [010]. The cohesion of the structure is dominated by van der Waals interactions. Related literature

New insights into the chemistry of di- and trimetallic iron dithiolene derivatives. Structural, Mössbauer, magnetic, electrochemical and theoretical studies

“…However, a nonbonding distance of 3. and [Fe 3 (CO) 7 (µ-SCH 2 CH 2 CH 2 S) 2 ]. 15 However, the four bond distances between the sulfur atoms and the internal iron atom [S(1)-Fe(1) of 2.208(2) Å and S(2)-Fe(1) of 2.196(1) Å] are shorter than the corresponding bond lengths between the sulfur and the external iron atoms [S(1)-Fe(2) of 2.305(2) Å and S(2)-Fe(2i) of 2.310(2) Å]. These differences can be attributed to the triple bridging mode of the dithiolene ligand in 3 which forces a bent Fe-Fe-Fe structure and a lengthening of the Fe-Fe bond.…”

“…0.15 Å shorter than the distances between the external Fe(2) atoms and their bonded sulfur atoms and the same tendency is also calculated for compound 4. Although a mixed valence Fe I Fe II Fe I state has been reported for [Fe 3 (CO) 7 (SRS) 2 (RvCH 2 CH 2 3,7 and CH 2 CH 2 CH 2 15 )] compounds in which each dithiolato is bridging two iron metals, the presence of two triple bridging "SC 6 H 2 Cl 2 S" groups in cluster 3 may also yield another mixed valence possibility such as Fe II Fe 0 Fe II . In order to gain insight a Mössbauer experiment has been carried out on compound 3.…”