Source of materialThis compound was synthesized by the hydroponic method. Cadmium(II) chloride (1.83 g, 0.01 mol) was dissolved in water (10 .ml). A N,N'-dimethylformamide solution (10 ml) of 2,2'-dithiosalicylic acid (3.06 g, 0.01 mol), 1,3-bis(4-pyridyl)propane (1.98 g, 0.01 mol) and sodium azide (0.65 g, 0.01 mol) was then added dropwise with stirring at 298 K. The reaction mixture was filtered and the filtrate allowed to stand for about five weeks until colorless single crystals were obtained. Block-shaped crystals suitable for X-ray diffraction were collected by filtration, washed with water and ethanol, and dried in air (1.55 g, 25 %yield).
Experimental detailsThe water Hatoms were refined subject to the restraint . Therefore, bpp has been frequently used as aspacer for the construction of the polymeric compounds. In the title crystal structure, each Cd(II) is six-coordinated, with bonds to four bpp ligands and two chlorine atoms, forming adistorted octahedron (figure, top). Bpp ligand acts as abridge to link two cadmium(II) ions through its two pyridine nitrogen atoms. Each cadmium(II) ion connects four bpp ligands to form an infinite 2D structure with (6,4) topology (figure, bottom). The cadmium(II) atoms, serve as nodes and the bpp ligands as rods. Thus, the network is based upon squares (CdL) 6 formed by six bpp ligands and six 4-connected cadmium(II) ions, forming 72-membered metallacyclic rings. Each of the four (Cdbpp) 6 grids are joined together through sharing the cadmium apices to give the final two-dimensional layer structure consisting of puckered rhombohedral grids with separation of about 13.870 Å based on the Cd···Cd distances. The most fascinating feature of the title compound is that each cadmium(II) ion connected to four other cadmium(II) ions, resulting in ad iamondoid network with the short symbol of 6 6 ,and the full vertex symbol of .6 2 .6 2 .6 2 .6 2 .6 2 . 6 2 .Two sets of 2D sheets, give rise to atwofold interpenetrating network. Moreover, the denser interpenetration happens by the interlock the two twofold interpenetrating networks. Four [6,4] diamond nets interpenetrate together to furnish the 4-fold interpenetration. Indeed, despite interpenetration, the coordination network still contains voids, filled by solvate molecules.
