Poly[tetra­aquadi‐μ3‐malonato‐cobalt(II)­calcium(II)]

The structure of the polymeric title compound, CaCo(C₃H₂O₄)₂(H₂O)₄]_n, consists of CaO₈ and CoO₆ polyhedra linked together by malonate groups. The Co atom lies on a centre of symmetry in an octa­hedral arrangement, and is coordinated by four malonate O atoms in a planar arrangement and two water mol­ecules in a trans conformation. The geometry around the Ca atom, which lies on a twofold axis, may be described as a distorted square anti­prism, which involves two water mol­ecules and six malonate O atoms. The Co—O and Ca—O bond lengths are in the ranges 2.0711 (12)–2.1004 (14) and 2.3775 (12)–2.6329 (12) Å, respectively.