Three-Dimensional Cd-MOF Based on Benzenetetracarboxilic Acid and Bis(imidazolylmethyl)benzene Ligands: Synthesis, Structure and Fluorescence Property

One new 3D metal-organic framework with formula [Cd(L)(0.5)(1,3-bib)(H2O)]center dot H2O (1) was prepared under hydrothermal conditions by employing the rigid 1,2,4,5-benzenetetracarboxilic acid (H4L) as the primary ligand and 1,3-bis(1H-imidazole-1-ylmethyl)benzene(1,3-bib) as the ancillary ligand. Complex 1 was characterized by elemental analysis, infrared spectroscopy, X-ray single crystal diffractometer, thermogravimetric analysis and X-ray powder diffractometer. The results show that complex 1 belongs to orthorhombic system, Pbca space group with cell parame- ters: a=0.857 08(4) nm, b=1.912 23(10) nm, c=2.451 60(12) nm. In complex 1, the carboxyl ligand L(4- )chelates the metal centers via bidentate mode. The metal centers are coordinated by L4- and 1,3-bib to form a three-dimensional structure. The fluorescent properties of 1 were studied. Complex 1 shows strong luminescent peak at 454 nm. The luminescence of complex 1 can be quenched b) acetone, MnO4- and Hg2+ ions, indicating that complex 1 was a good sensor for them.