| The coordination polymer is a kind of important organic/inorganic hybrid material which has potential applications in many fields. Because of that it has won more and more attention. The aim of this paper is to study the rule of the synthesis of coordination polymers, the structures and the related performances of the coordination polymers. Nine coordination polymers with novel structures have been synthesized by hydrothermal and common solution synthesis using the ligands containing N and O atoms, and their structures and the related performances have been investigated by means of single-crystal X-ray diffraction methods, elemental analysis (EA), infrared spectra (IR), thermogravimetric and differential thermal analysis (TG-DTA).Firstly, the coordination polymers with ligands of terephthalic acid and imidazole were prepared. Under the conditions of the common solution synthesis, three coordination polymers with novel structures, [Ni(BDC)(Im)3(H2O)]n(1), [Co(Im)4(H2O)2]n·n(BDC) (2) and [Cd(BDC) (Im)4]n (3) were synthesized by the reaction of dicarboxylates acid, imidazole and transition metal cations. This observation combining the experimented results suggests that: (a) Due to the weak acidity and less solubility of dicarboxylates acid and their complexes, the conditions to synthesize its coordination polymers are relatively critical, especially pH value of the reaction system, (b) The concentration of imidazole should be moderate, or the ion of [M(Im)4(H2O)2]2+ (M=Ni2+, Co2+, Cd2+) may be easily formed.The coordination polymers with the mixture of 1,4-fumaric acid and imidazole were prepared. Under the conditions of the common solution synthesis, two coordination polymers [Cd(C4H2O4) (Im))3]n-2nH2O (4) and [Zn(C4H2O4)(Im)2(H2O)]n (5) were synthesized. The results are obtained as follows: (a) The structures of (4) and (5) both show that the metal ions are linked by fumarate as bridging ligands to afford one-dimensional frameworks, and then infinite three-dimensionalsupramolecular networks are formed through hydrogen bonding interactions, (b) Coordination polymer (4) possesses a better fluorescence performance.The coordination polymers with ligand of 3-(3-pyridyl)acrylate acid were prepared under the condition of the hydrothermal synthesis. Two polymers (6) and (7) are isomers. They exhibit entirely different 3-D framework structures. The coordinaton polymer (7) possesses a 3-D framework structure with a size of 8.47 X 8.99A along b axis.The coordinaton polymers with the mixture of dicarboxylic acid ligands (1,4-fumaric acid and sebacic acid) and 1,10-phen were prepared. Under the condition of the hydrothermal synthesis, the coordination polymer [Co2(C4H2O4)2(phen)2]n (8) was synthesized with the mixture of 1,4-fumaric acid, 1,10-phen and Co2+. However, the coordination polymer [Ni(CioHi6O4)(phen) (H2O)2]n-nH2O (9) was prepared with the mixture of sebacic acid, 1,10-phen and Ni2+ under the common solution synthesis. Eight-rings and twenty-eight-rings were formed through the connection of fumarate with the ions in the structure of coordination polymer (8). The characterization of (8) by N2 adsorption shows that the BET surface area is 24.2m /g. The coordination polymer (8) possesses micropore structure and better thermal stabilization which makes it possible to become a micropore material. |
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