Crystal structure of the coordination polymer [FeIII2{PtII(CN)4}3]

The title complex, poly[dodeca-μ-cyanido-diiron(III)triplatinum(II)], [FeIII2{PtII(CN)4}3], has a three-dimensional polymeric structure. It is built-up from square-planar [PtII(CN)4]2− anions (point group symmetry 2/m) bridging cationic [FeIIIPtII(CN)4]+∞ layers extending in the bc plane. The FeII atoms of the layers are located on inversion centres and exhibit an octahedral coordination sphere defined by six N atoms of cyanide ligands, while the PtII atoms are located on twofold rotation axes and are surrounded by four C atoms of the cyanide ligands in a square-planar coordination. The geometrical preferences of the two cations for octahedral and square-planar coordination, respectively, lead to a corrugated organisation of the layers. The distance between neighbouring [FeIIIPtII(CN)4]+∞ layers corresponds to the length a/2 = 8.0070 (3) Å, and the separation between two neighbouring PtII atoms of the bridging [PtII(CN)4]2− groups corresponds to the length of the c axis [7.5720 (2) Å]. The structure is porous with accessible voids of 390 Å3 per unit cell.