Poly[tetrakis(μ-1,1,1,3,3,3-hexafluoropropan-2-olato)iron(II)dipotassium].

The title compound, [K2Fe{OCH(CF3)2}4] n , was formed from the reaction of potassium hexa-fluoro-isopropoxide with iron(II) chloride in toluene. The Fe(II) atom has a highly distorted tetra-hedral coordination environment. All four of the non-equivalent hexa-fluoro-isoprop-oxy O atoms link the Fe(II) atoms to one of the K(+) atoms in an alternating chain of Fe-O-K-O fused four-membered rings, with K-Fe distances of 3.715 (2) and 3.717 (2) Å. This K(+) atom is also bridged to eight of the F atoms. The other K(+) atom is bonded to only two of the O atoms, but has seven short K⋯F contacts, one of which links the chains into a three-dimensional arrangement. Weak hydrogen bonding between the lone H atoms on the hexa-fluoro-isoprop-oxy groups and F atoms is also present. The crystal studied was refined as an inversion twin.