SYNTHESIS, CRYSTAL AND MOLECULAR-STRUCTURE AND MAGNETIC-PROPERTIES OF BIS[(MU-HYDROXO)BIS(MU-2,5-DIAMINO-1,3,4-THIADIAZOLE-N-1, N-2-CHLOROAQUA(2,5-DIAMINO-1,3,4-THIADIAZOLE-N-1)COBALT(II)-O,N-1, N-1]-COBALT(II) DICHLORIDE DIHYDRATE

The reaction product of cobalt(II) chloride and 2,5-diamino-1,3,4-thiadiazole was prepared and characterized by means of structural, magnetic and spectroscopic measurements. The crystals are monoclinic, space group P2(1)/c, with a = 10.619(1), b = 12.503(1), c = 15.802(2) angstrom, beta = 104.98(1)-degrees, and Z = 2. The structure was solved by the heavy-atom method, and least-squares refinement of structural parameters led to a conventional R factor of 0.043 for 1236 independent reflections. The structure consists of centrosymmetric trimeric discrete molecules in which the central cobalt atom is coordinated in slightly distorted octahedral geometry by four nitrogen and two oxygen atoms, and the thermal cobalt atoms by three nitrogen, two oxygen and one chlorine atoms. The central cobalt atom is joined to each terminal cobalt ion by two planar triazole bridging molecules and one bridging hydroxide. The nearest-neighbor Co-Co distance is 3.360(2) angstrom. The magnetic susceptibility of the complex is compared with other trinuclear compounds bridged by triazolate ligands.