Poly[di-μ9-citrato-tetrasodiumzinc]

Abstract

In the title compound, [Na4Zn(C6H5O 7)2] n, the ZnIIion lies on an inversion center and is coordinated by six O atoms from two citrate ligands, forming a distorted octahedral geometry. There are two crystallographically independent Na +cations in the asymmetric unit. One Na+cation exhibits a distorted square-pyramidal geometry defined by five O atoms from four citrate ligands. The other Na+cation is surrounded by six O atoms from five citrate ligands in a distorted octahedral geometry. The Na+cations are bridged by citrate carboxylate groups, forming a layer parallel to (100). The layers are further assembled into a three-dimensional network with the [Zn(citrate)2]4-building units as 'pillars'; O-H⋯O hydrogen bonds also stabilize the structure.