| Recently, the construction of coordination polymers with carboxyl and N-containing heterocyclic ligands has been a field of rapid growth not only for their intriguing architectures and topologies but also for their applications in areas of catalysis, sorption, nonlinear optical property, luminescence and magnetism, etc. 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. At the same time, crystalline materials can be endowed with optics, electric, magnetism, enantioselective separation and catalysis by selecting functional metal ions and organic ligands with functional groups. In this paper, transition metal or lanthanide and carboxyl and N-containing ligands have been selected to synthesize three series of coordination polymers in order to study on the effect factors influencing the structure of the coordination polymers, such as solvent, pH and temperature etc. of the final products at hydrothermal conditions. We have yielded 21 coordination polymers. The XRD, IR, TG-DTA, fluorescence spectra and magnetism have also been studied, which would take an important role in the explorations of structures and functions for coordination polymers. The paper can be divided into six chapters.In the first chapter, the concepts, histories, new developments and the current sorts of coordination polymers are concisely introduced, as well as the lanthanide coordination polymers with carboxyl ligands and the hydrothermal in situ ligand syntheses. 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, the principle, methods and the reagent used in the syntheses are summarized by the large.In the third chapter, six new coordination compounds prepared through in situ ligand syntheses: [Zn2(bim)4]n (1),[Co2(H2bbim)4(bbim)]Cl2 (2), [M(H2bbim)(1,4-BDC)]n (M=Zn (3), Co(4)), [M4(H2bbim)9(ox)3(OH)2]n (M= Co(5), Fe(6)) (Hbim = benzimidazole,H2bbim=2,2'-bisbenzimidazole, 1,4-H2BDC=1,4-benzenedicarboxylic acid,ox = oxalate), have been in detail described. Two different ligands Hbim and H2bbim were generated via the hydrothermal in situ cyclizative condensation reactions of o-phenylenediamine and oxalic acid during formation processes of compounds 1-6. Besides cyclizative condensation reaction, there exists C-C bond rupture in the formation process of Hbim. In 1,bim ligands bridge Zn atoms into a single-stranded helical chain which are linked through metal-ligand interactions to generate a 2-D grid-like structure. And through weak C-H…πinteractions, the neighboring 2-D layer are formed into a 3-D supramolecular network. 2 features a dinuclear structure due to the large steric hinderance of H2bbim ligand. Through N-H…Cl hydrogen bonds, the dinuclear units of 2 are alternately arranged to afford a unique 1 -D helical chain. Compounds 3 and 4 are isostructural and display 1-D chain structure consisting of M(H2bbim)2+ (M = Co/Zn) units linked by 1,4-BDC ligands. The isostructural compounds 5 and 6 contain two units with different coordination environments: [M(H2bbim)(ox)] unit (Ml unit) and [M(H2bbim)3]2+ unit (M2 unit) (M=Co(5), Fe(6)). Through N-H…O and O-H…O hydrogen bonds, Ml units are linked to form an interesting supramolecular network with hexagonal channel in [111] direction. And the hexagonal channels are filled with M2 units which are connected with Ml units through N-H…O hydrogen bonds. In the view of topology of compounds 5 and 6, 4-connected and 3-connected nodes are interlinked to form 3-D supramolecular network with Schlafli symbol (86)3·83.Compounds 1-6 are the first examples of coordination polymers constructed from in situ generated Hbim and H2bbim ligands.Compounds 1 and 3 possess good fluorescence emissions in visible region and both of the emission bands can tentatively be assigned to ligand-to-metal charge transfer (LMCT). Temperature-dependent magnetic susceptibility measurements for compounds 2 and 4 indicate the presence of ferromagnetic interactions between Co(Ⅱ) ions.In the fourth chapter, ten lanthanide coordination polymers with mixed polycarboxylate ligands have been synthesized and characterized by elemental analysis,IR, TGA and single-crystal X-ray diffraction. Six lanthanide coordination polymers are constructed from o-phthalate and oxalate ligands: [Ln2(op)2(ox)(H2O)4]n·nH2O (Ln = Ce, Pr, Nd, Sm,Eu and Gd for 7-12, respectively);two are constructed from pyromellitate and oxalate ligands: [KLn(pma)1/2(ox)(H2O)]n (Ln = Tb (13) and Dy (14)) and the other two are from m-phthalate and oxalate ligands: [KLn2(mp)3(ox)1/2(H2O)3]n (Ln = Ce(15) and Pr(16)) (op = o-phthalate, H2ox = oxalate, pma = pyromellitate and mp= m-phthalate). Compounds 7-12 show (3,4)-connected 2-D network structures consisting of {Ln(op)}n staircase chains bridged by ox ligands. Compounds 13 and 14 consist of 1-D zigzag {Dy(ox)}n chains linked by pma ligands adopting a newμ4-hexadentate coordination mode to form 2-D 6-connected networks with (36·46·53) topology. Through K…O interactions, the 2-D networks are further connected to construct 3-D structures. Compounds 15 and 16 display inorganic-organic 3-D topology networks with the Schl(a|¨)fli symbol (3·43·52)(32·410·59·614·7)(42·5) containing mixed (3,4,9)-connected nodes. They are the first examples of lanthanide-carboxylate coordination polymers with mixed (3,4,9)-connected nodes.Compounds 11,13 and 14 present characteristic emission of Eu(Ⅲ), Tb(Ⅲ) and Dy(Ⅲ) in the visible region, respectively. Temperature-dependent magnetic susceptibility measurements for compounds 7, 9 and 14 indicate there are antiferromagnetic interactions between metal centers.In the fifth chapter, five lanthanide coordination polymers with mixed aliphatic polycarboxylate ligands: [MLn2(NTA)(ox)2(H2O)5]n (M = K, Ln = Ce, Pr, Gd, Tb for 17,18,19 and 20; M=Na, Ln = Pr for 21; NTA = nitrilotriacetate, ox = oxalate) have been synthesized and characterized by elemental analysis, IR,TGA and single-crystal X-ray diffraction. X-ray structural analysis reveals that compounds 17-21 are isomorphous and possess 3-D frameworks with 1-D channels along a axis. The Pr(Ⅲ) ions, NTA and ox ligands act as walls of the channels, while K ions and the coordinated water molecules filled the channels. The structures of17-21 can be described as an unprecedented trinodal (4,4,4)-connected (65·8)(43·63)(4·65) topological network.Temperature-dependent magnetic susceptibility measurements for compounds 18 and 19 indicate there are antiferromagnetic interactions between metal centers.In the sixth chapter, a brief conclusion and outlook of this thesis are given.
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