Poly[[μ-aqua-aqua­[μ(4)-ethyl (dichloro­methyl­ene)diphospho­nato]sesqui­calcium(II)] acetone hemisolvate 4.5-hydrate]

The title compound, {[Ca(1.5)(C(3)H(5)Cl(2)O(6)P(2))(H(2)O)(2)]·0.5CH(3)COCH(3)·4.5H(2)O}(n), has a two-dimensional polymeric structure. The asymmetric unit contains two crystallographically independent Ca(2+) cations connected by a chelating and bridging ethyl (dichloro­methyl­ene)diphos­pho­n­ate(3(−)) ligand and an aqua ligand. One of the Ca atoms, lying on a centre of symmetry, has a slightly distorted octa­hedral geometry, while the other Ca atom is seven-coordinated in a distorted monocapped trigonal-prismatic geometry. The polymeric layers are further connected by extensive O—H⋯O hydrogen bonding into a three-dimensional supra­molecular network. The acetone solvent mol­ecule and one uncoordin­ated water mol­ecule are located on twofold rotation axes.