Two Tartrate-Pillared Coordination Polymers: Hydrothermal Preparation, Crystal Structures, Spectroscopic and Thermal Analyses of {[M2(μ-C4H4O6)2(H2O)] • 3H2O}∞ (M = Mn, Cd)

Two novel three-dimensional coordination polymers, formulated as {[M-2(mu-C4H4O6)(2)(H2O)] center dot A 3H(2)O}(a) (M = Mn for 1 and Cd for 2), have been synthesized under hydrothermal reaction condition. Both complexes were characterized by elemental analysis and IR spectroscopy. Their molecular and crystal structures were determined by X-ray crystal structure analysis and their thermal stability by TGA-DTA methods. Compound 1 crystallizes in the monoclinic space group, P2(1), while compound 2 crystallizes the orthorhombic space group, P2(1)2(1)2(1). The structures are self-assembled from bifunctional tartrate and water molecules. Tartrate ligands in 1 and 2 contribute to both covalent and hydrogen bonds. Polymeric chains of 1 and 2 are composed of M(II) ions bridged by tartrate ions in O,O' fashion. The asymmetric units of coordination polymers contain two metal centers having different coordination environments.