Poly[[hexa­aqua­bis­(μ₃-pyrimidine-4,6-dicarboxyl­ato)dicalcium] dihydrate]

The polymeric structure of the title compound, {[Ca₂(C₆H₂N₂O₄)₂(H₂O)₆]·2H₂O}_n, is built up of mol­ecular layers composed of Ca^II ions bridged by both ligand N and O atoms with one of the O atoms being bis-monodentate. Two adjacent Ca^II ions are bridged by these O atoms, forming a centrosymmetric dimer which is the building unit of the structure. The dimers are nodes of a cross-linked mol­ecular layer parallel to (101). The Ca^II ion is coordinated by two bidentate ligands, one monodentate ligand and three water mol­ecules in the form of a distorted polyhedron with a coordination number of eight. Solvate water mol­ecules located between adjacent layers participate as donors and acceptors in a system of hydrogen bonds in which coordinating water mol­ecules also act as donors and non-coordinating carboxyl­ate O atoms act as acceptors.