| Crystal engineering is involved with the behavior of molecules or chemical groups within the crystal lattice, the control of crystal design and properties, and the prediction of crystal structures. Recently, the new research fields in the crystal engineering contain inorganic-organic hybrid material, microporous material, molecular magnet and coordination polymers, et al. The design and synthesis of coordination polymers with unusual structures and properties are attracting increasing attention, not only for their interesting molecular topologies, but also for their potential applications as functional materials. According to the principle of crystal engineering, it is possible that rational design and synthesis of crystalline materials by selecting certain geometric metal ions and special organic ligands. The aim of this work is to design and synthesize a series of metal-organic carboxylate coordination polymers. Their luminescent and magnetism were also studied.In the first chapter, the concepts, methods, histories and new developments of coordination polymers are concisely introduced. At the end of this chapter, we pointed out the importance of the search project and summarized the important results obtained in the thesis.In the second chapter, four new rare earth compounds, [Eu(NDC)1.5(DMF)2] 1, [Nd2(NDC)3(DMF)4]·H2O 2, [La2(NDC)3(DMF)4]·0.5H2O 3 and [Eu(BTC)(H2O)] 4, where NDC = 1,4-naphthalenedicarboxylate, BTC = 1,3,5-benzenetricarboxylate and DMF = N,N-dimethylformamide, have been synthesized through pre-heating and cooling-down crystallization. Compounds 1, 2 and 3 possess similar 2-dimensional (2D) structures, in which the NDC ligands link M(III) (M=La, Nd and Eu) ions of two adjacent double chains constructed by NDC ligands and dinuclear M(III) building units. In compound 4 the Eu(III) ion is seven-coordinated by oxygen atoms from six BTC and one terminal water molecule in a distorted pentagonal bipyramidal coordination environment. If the BTC ligand and the Eu(III) ion are regarded as six-connected nodes, respectively, the structure of compound 4 can be well described as a 3D six-connected net. Furthermore, compounds 1 and 4 exhibit strong red luminescence upon 355 nm excitation. Compound 2 displays interesting emissions in the near-IR region, and yellow (580 nm) pumping of this compound results in ultraviolet and intense blue emissions through an up-conversion process. The magnetic properties of compounds 1, 2 and 4 have been studied through measuring their magnetic susceptibilities over the temperature range of 4–300 K.In the third chapter, a series of PbII coordination polymers [Pb(NDC)(DPP)] 1, [Pb(NDC)(PTCP)]·0.5H2O 2, [Pb(NDC)(DPPz)] 3, [Pb(NDC)(TCPN)2] 4, [Pb2(NDC)2(TCPP)] 5, [Pb(HNDC)2]·H2O 6, [Pb(NDC)(DMA)] 7, [Pb(BDC)(DMA)] 8, [Pb(trans-CHDC)(H2O)] 9, and [Pb2(cis-CHDC)2]·[NH(CH3)2] 10, where NDC = 1,4-naphthalenedicarboxylate, DPP = 4,7-diphenyl-1,10-phenanthroline, PTCP = 2-phenyl-1H-1,3,7,8,-tetraaza-cyclopenta[l]phenanthrene, DPPz = dipyrido[3,2-a:2',3'-c]-phenazine, TCPN = 2-(1H-1,3,7,8-tetraaza-cyclopenta[l]phenanthren-2-yl)-naphthol, TCPP = 4-(1H-1,3,7,8-tetraaza-cyclopenta[l]phenanthren-2-yl)-phenol, DMA = N,N-dimethylacetamide, BDC = 1,4-benzenedicarboxylate, and CHDC = 1,4-cyclohexanedicarboxylate, have been synthesized from a hydrothermal or solvothermal reaction system through varying the ligands or the solvents. Compounds 1-5 crystallize in the presence of a N-donor chelating ligand (NCL) as well as an aromatic dicarboxylate linker. Compounds 1-4 are 1-D polymers with differentπ-πstacking interactions whereas compound 5 consists of 2-D layers. The structures of compounds 7, 8 and 10 are 3-D frameworks formed through connection of the PbII centers by organic acid ligands. Among these compounds, 7 is chiral although the NDC ligand is achiral whereas the framework of 8 is a typical 3-D (3,4)-connected net. Compound 10 is the first example with PbII wheel cluster [Pb8O8] units bridged by carboxylate groups. Compound 6 contains 1-D chains which are further extended to a 3-D structure byπ-πinteractions. Compound 9 consists of a 2-D network constructed by PbII centers and trans-CHDC ligands. The structural difference between 7 and 8, and between 9 and 10 indicates the importance of solvents for the framework formation of the coordination polymers. Through varying solvent the cis and trans conformations of H2CHDC in 9 and 10 have been separated completely. The photoluminescence and nonlinear optical properties of the coordination polymers have also been investigated.In the fourth chapter, three novel interesting coordination polymers, [Cd2Cl2(fum)(ptcp)2] 1, [Cd2(fum)2(tcpp)2]·H2O 2, and [Cd3(adip)3(ptcp)2] 3, where fum = fumarate and adip = adipate, have been successfully isolated under hydrothermal conditions and structurally characterized. Polymer 1 exhibits an infinite 1D chain structure, which is further stacked via strongπ-πinteractions to form 3D supramolecular architectures. Polymers 2 and 3 feature 2D layer structures, which are further interconnected byπ-πinteractions to result in 3D supramolecular architectures. The three coordination polymers are interestingly regulated by dicarboxylates and N-donor chelating ligands (NCLs), and the ligand effects on compound architectures are also unraveled.
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