[MII(3-(2′-pyridylmethyleneamino)pyridine)(NO3)2], (M = Co, Zn, Cd) coordination polymers; single, mixed and composite crystals

3-(2′-Pyridylmethyleneamino)pyridine (L) and its homo and heterometallic coordination polymers [ML(NO3)2]n, (M = Co, Zn, Cd; 1–3) and [MM′L2(NO3)2]n, (M, M′ = Co, Zn, Cd; 4–6) have been synthesized and characterized by CHN analysis, IR and UV–Vis spectroscopy. The crystal structures of the compounds were determined from single crystal X-ray diffraction. Structural studies of compounds revealed the crystals are isomorphous (monoclinic, P 21/c). The coordination polyhedron about the M(II) center in the compounds is best described as distorted octahedral. Each L is chelated to a metal center (M) and also linked to another metal atom to form an infinite helical chain along the b axis. The formation of a series of composite crystals based on epitaxial growth of crystalline layers on preformed crystals has also been reported. The crystal growth of the zinc compound was also studied in the presence of KI. Thermogravimetric investigations of the compounds have also been discussed.

Graphical abstract3-(2′-Pyridylmethyleneamino)pyridine and its homo and heterometallic coordination polymers have been synthesized and characterized. A series of composite crystals based on epitaxial growth were prepared. Thermal and fluorescence properties of ligand and complexes have been studied and compared.Figure optionsDownload full-size imageDownload as PowerPoint slide