Synthesis and Crystal Structure of Complex: [Co(cdm)_2(H_2O)_4].2H_2O (cdm=Carbamyldicyanomethanide Anion)

1 INTRODUCTION Crystal engineering and the design of solid-state architectures have recently become areas of increasing interest[1, 2]. Such crystal engineering may afford new materials with useful properties such as catalytic activity, micro-porosity, nonlinear optical activity, cooperative magnetic behavior and so on. Polynitrile-ligand is one of the ideal multi-functional ligands for crystal engineering and many complexes with polynitriles as ligands have been found to show the spe…

Synthesis and Crystal Structure of Complex: [Co(cdm)2(H2O)4]·2H2O(cdm = Carbamyldicyanomethanide Anion)

Mononuclear complex [Co(cdm)2(H2O)4]?H2O was synthesized by sodium carbamyldicyanomethanide (Nacda) and cobalt perchlorate. The crystal belongs to monoclinic system, space group P21/n with a = 9.366(3), b = 7.392(3), c = 12.039(4)? = 108.335(4)? V = 791.2(5)?, Z = 2, Mr (C8H16CoN6O8) = 383.2, Dc = 1.608 g/cm3, F(000) = 394, = 1.135 mm-1, = 0.71073 ? The structure was refined to R = 0.0240 and wR = 0.0632 for 1267 observed reflections (I > 2(I)). The cobalt(II) atom in the complex is coordinated by two nitrile-nitrogen atoms and four oxygen atoms of H2O, which forms a slightly distorted coordination octahedron around the cobalt(II) ion. The mononuclear complexes are connected by hydrogen bondings and in the crystal there exists a cavity where the uncoordinated H2O molecules are trapped.