(η⁵-Cyclopentadienyl)[(1,2,3,4,4a,10a-η)-1-methylthianthrene]iron(II) hexafluoridophosphate acetone 0.33-solvate

The title complex salt, [Fe(C₅H₅)(C₁₃H₁₀S₂)]PF₆·0.33C₃H₆O, obtained from an acetone–diethyl ether–dichloromethane mixture at 280 (2) K, has three cationic molecules (A–C), three hexafluoridophosphate counter-anions and one acetone solvent molecule in the asymmetric unit. Two of the three cations contain FeCp (Cp is cyclopentadienyl) inside the fold of the heterocycle. The dihedral angles between the planes of the external (complexed and uncomplexed) benzene rings in the thianthrene molecule are 146.5 (2)° for FeCp-out-of-fold molecule A, and 139.0 (3) and 142.5 (2)° for the two FeCp-in-fold molecules B and C, respectively. The complexed Cp and benzene rings in each molecule are almost parallel, with a dihedral angle between the planes of 0.2 (5)° for molecule A, 2.8 (5)° for B, and 2.19 (4) and 6.86 (6)° for the disordered Cp ring in C.