title: Poly[bis-(μ(2)-pyrimidine-2-carboxyl-ato-κO,N:O',N')calcium].
abstract: 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.
authors.affiliation: Department of Chemistry, Zhejiang University, People's Republic of China.
authors.forename: Bing-Yu
authors.initials: BY
authors.lastname: Zhang
authors.forename: Jing-Jing
authors.initials: JJ
authors.lastname: Nie
authors.forename: Duan-Jun
authors.initials: DJ
authors.lastname: Xu