catena-Poly[[diaqua­cobalt(II)]-bis­(μ-4-fluoro­benzoato-κ(2) O:O′)]

The hydro­thermal reaction of CoCO(3) and 4-fluoro­benzoic acid afforded the title Co(II) complex, [Co(C(7)H(4)FO(2))(2)(H(2)O)(2)](n). The Co(II) atom is located on an inversion center and is coordinated by six O atoms from two water mol­ecules and four μ(2)-carboxyl­ate groups of 4-fluoro­benzoate anions, forming a distorted CoO(6) octa­hedron, with Co—O bond lengths in the range 2.071 (2)–2.130 (2) Å. All adjacent O—Co—O angles are in the range 84.78 (6)–95.22 (6)° and opposite angles are 180.0°. Each μ-carboxyl­ate group of the 4-fluoro­benzoate anions bridges two symmetry-related Co(II) atoms. Hydrogen-bonding inter­actions of the coordinated water mol­ecules further connect the cobalt–carboxyl­ate units, forming layers perpendicular to the a axis. The cobalt–oxygen layers are encased in a sandwich-like fashion by layers of π-stacked 4-fluoro­benzoate anions. Within these layers the benzene rings of the 4-fluoro­benzoate anions are π-stacked, with centroid–centroid distances of 3.432 (4) Å.