Structural diversity in the Cu(pyrazinecarboxylate)2/CdCl2 system:: new one-, two- and three-dimensional mixed metal coordination polymers

Four new inorganic-organic polymeric materials have been synthesized by reacting the metal containing building block, Cu(pyzca)(2), with cadmium chloride. All resulting polymers have both metals incorporated in the structure and display a variety of structural motifs, ranging from one-dimensional chains to complicated three-dimensional networks. The first compound, [Cu(Pyzca)(2)(H2O)CdCl2(H2O).H2O](n) (1) is a one-dimensional double chain. The next two compounds, [Cu(Pyzca)(2)(H2O)(2)Cd2Cl4(H2O)(2)] n (2) and [Cu(Pyzca)(2)(H2O)Cd2Cl4(H2O)(2).3H(2)O](n) (3), assemble in a two-dimensional brick-wall network, while the fourth, [Cu(Pyzca)(2)Cd2Cl4](n) (4), features an intricate three-dimensional network. Synthesis, X-ray structure determinations, and the influence of water molecules coordinated to the copper centers on the coordination geometry and overall extended structure are discussed.