Synthesis, Crystal Structure and Luminescence Properties of a Cadmium(II) Complex Based on 2-Hydroxy-6-methylisonicotinic Acid

A new cadmium(II) complex [Cd(Hminic)(IP)](n) (1, Hminic = 2-hydroxy-6-methylisonicotinic acid, IP = imidazo[4,5-f]-1,10-phenanthroline), has been synthesized by the reaction of a Hminic and auxiliary N-containing ligands with Cd(II) ion under hydrothermal conditions. The complex was studied by elemental analysis, IR spectroscopy and X-ray crystallography. It is formulated as C20H13CdN5O3, crystallizes in monoclinic system, space group C2/c with a = 9.6764(8), b = 26.767(2), c = 14.1332(11) angstrom and beta = 97.4510(10)degrees. V = 3629.7(5) angstrom(3), Z = 8, M-r = 483.75, D-c = 1.770 g/cm(3), F(000) = 1484 and mu = 1.237 mm(-1). The final refinement gave R = 0.0309 and wR = 0.0703 for 4151 reflections with I > 2 sigma(I). In the structure of 1, two Cd(II) atoms are joined by a pair of mu(2)-hydroxyl oxygen atoms giving rise to a dinuclear Cd(II) unit which is bridged by Hminic linkers to form a 1D ladder-like polymer chain. The chelating ligand IP coordinated to the Cd(II) atom, and alternately attached to both sides of the ladder-like polymer chain. Adjacent chains are further bound together by strong intermolecular hydrogen bonds and face-to-face pi center dot center dot center dot pi interactions, resulting in the formation of a 3D supramolecular architecture. Furthermore, the thermal stability and luminescent properties of this complex and the free ligands have been investigated.