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

The trinuclear title compound, [Fe₃(C₃H₆S₂)₂(CO)₇], is a mixed-valent Fe^I/Fe^II complex and crystallizes with two mol­ecules of similar configuration in the asymmetric unit. The three Fe atoms in each mol­ecule display a bent arrangement [Fe—Fe—Fe = 156.22 (4) and 157.06 (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.