A twofold interpenetrating three-dimensional Cd(II) coordination framework: poly[[μ2-1,3-bis(2-methyl-1H-imidazol-1-yl)benzene](μ3-5-nitrobenzene-1,3-dicarboxylato)cadmium(II)].

A twofold interpenetrating three-dimensional Cd(II) coordination framework, [Cd(C8H3NO6)(C14H14N4)]n, has been prepared and characterized by IR spectroscopy, elemental analysis, thermal analysis and single-crystal X-ray diffraction. The asymmetric unit consists of a divalent Cd(II) atom, one 1,3-bis(2-methyl-1H-imidazol-1-yl)benzene (1,3-BMIB) ligand and one fully deprotonated 5-nitrobenzene-1,3-dicarboxylate (NO2-BDC(2-)) ligand. The coordination sphere of the Cd(II) atom consists of five O-donor atoms from three different NO2-BDC(2-) ligands and two imidazole N-donor atoms from two different 1,3-BMIB ligands, forming a distorted {CdN2O5} pentagonal bipyramid. The NO2-BDC ligand links three Cd(II) atoms via a μ1-η(1):η(1) chelating mode and a μ2-η(2):η(1) bridging mode. The title compound is a twofold interpenetrating 3,5-connected network with the {4(2).6(5).8(3)}{4(2).6} topology. In addition, the compound exhibits fluorescence emissions in the solid state at room temperature.