Magnetic properties and luminescence sensing of five coordination polymers based on a rigid terphenyl-tetracarboxylic acid

Herein, five coordination polymers, namely {[Ni-2(tptc)(4,4'-bibp)(2)]center dot 2H(2)O center dot 2cyclohexanol}(n) (1), {[Co-2(tptc)(4,4'-bibp)(2)]center dot 2H(2)O center dot 2cyclohexanol}(n) (2), {[Zn-2(tptc)(1,2-bimb)(2)]}(n) (3), {[Co(tptc)(0.5)(1,4-bib)]center dot H2O .DMF}(n) (4), and {[Co-2(tptc)(1,2-bimb)(H2O)]center dot H2O}(n) (5) (H(4)tptc = terphenyl-3,3, 5,5-tetracarboxylic, 4,4'-bibp = 4,4'-bis(imidazolyl)biphenyl, 1,4-bib = 1,4-bis(imidazol-1-yl)benzene, and 1,2-bimb = 1,2-bis(imidazol-1-ylmethyl)benzene) were successfully constructed based on a rigid terphenyl-tetracarboxylic acid ligand and N-containing auxiliary ligands under solvothermal conditions. Their structures were determined by single-crystal X-ray diffraction and further characterized by elemental analyses, IR spectroscopy, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analyses. Complexes 1 and 2 involved a new 4,6-c 3D network structure. Complex 3 displayed an open 3D structure with the bbf topological type. Complex 4 involved an extended 3D (4,6)-c network with the point symbol of {4(4).6(10).8}{4(4).6(2)}. Complex 5 had a 2D framework with the dinuclear [Co-2(COO)(2)] SBUs. The variable-temperature magnetic susceptibilities of complexes 1, 2, 4, and 5 were also investigated, and the results indicated that the isophthalic acid bridge exhibited weak ferromagnetic coupling. Moreover, the fluorescence experiments showed that complex 3 had a potential application in the sensing of small organic molecules.