Crystal structure of a heterometallic coordination polymer: catena-poly[[[tetra­aqua­cobalt(II)]-μ-pyridine-2,6-di­carboxyl­ato-calcium(II)-μ-pyridine-2,6-di­carboxyl­ato] dihydrate]

In the crystal of the title polymeric complex, {[CoCa(C(7)H(3)NO(4))(2)(H(2)O)(4)]·2H(2)O}(n) (1), the Co(II) ion is N,O,O′-chelated by two pyridine-2,6-di­carboxyl­ate anions in a distorted N(2)O(4) octa­hedral geometry, and two carboxyl­ate O atoms of pyridine-2,6-di­carboxyl­ate anions bridge tetra­aqua­calcium(II) units to form polymeric chains propagating along the b-axis direction. In the crystal, O—H⋯O and C—H⋯O hydrogen bonds, and offset π–π stacking inter­actions [inter­centroid distances = 3.551 (1) and 3.746 (1) Å] involving inversion-related pyridine rings link the polymeric chains and lattice water mol­ecules to form a supra­molecular three-dimensional framework.