Two novel isomeric organic anion-water aggregations: 1D tape and 3D 2-fold interpenetrated diamond network

Two novel hydrogen-bonded isomeric water-imdn aggregations were observed in two Co(II) coordination compounds, formulated as {[Co(2,2'-bpy)(3)][(imdn)(2)(H2O)(4)]}(1) and {[Co(4,4'-bpy)(2)] [(imdn)(2)(H2O)(4)]}(n)(2) (bpy = bipyridine, Himdn = 2H-imidazole-4,5-dicarbonitrile). The water-imdn aggregation in 1 is a 1D hydrogen-bonded tape based on an octamer water cluster. For 2, two imdn and four water molecules are hydrogen bonded to an unprecedented bag-like binary supramolecular cluster which acts as a tetrahedral node to be hydrogen-bonded to its four neighbors, giving a 3D network with a diamond topology. Two translationally equivalent diamond networks mutually interpenetrate each other to form the resulting 2-fold diamond network. The different host structural motifs are responsible to the dissimilarity of two isomeric water-imdn aggregations.