Poly[bis(μ2-pyrimidine-2-carboxylato-κ4O,N:O′,N′)calcium]

In the crystal structure of the title polymeric complex, [Ca(C(5)H(3)N(2)O(2))(2)](n), the Ca(II) cation has site symmetry m2 and is N,O-chelated by four pyrimidine-2-carboxyl-ate anions in a square-anti-prismatic geometry. The planar pyrimidine-2-carboxyl-ate anion is located on a crystallographic special position, three C atoms have site symmetry 2mm, while the carboxyl O atom, the pyrimidine N atom and the other C atom have site symmetry m. Each pyrimidine-2--carboxyl-ate anion bridges two Ca(II) cations, forming polymeric sheets extending parallel to (001). π-π stacking exists between parallel pyrimidine rings [centroid-centroid distance = 3.6436 (6) Å] of adjacent polymeric sheets. Weak C-H⋯O hydrogen bonding is also observed between these sheets.