| The chemistry of novel metal-organic hybrid coordination polymers has been the subject of intensively researched area in recent years, due to their interesting topologies and unexpected properties for potential applications. Recent advances in this field have led to many ordered coordination networks formed through the deliberate selection of functionalized organic ligands and coordination geometries of transition metal ions. And many of them are regarded as promising materials for applications in catalysis, separation, gas storage, and molecular recognition.In this manuscript, we use poly-pyridyl and carboxylate based ligands to synthesized four series of supramolecular complexes by different synthetic methods, they are polynuclear metal complexes coordination polymers cluster polymers and supramolecular complexes, respectively. And we further studied their magnetic and third order nonlinear optical (NLO) properties.In Chapter II, the ligand N,N'-bis-(l,3,4-thio-biazole)-2,6-pyridyldicarboxamide (btapca) has been synthesized and its coordination properties toward La(III) and Ce(III) in the presence of air have been investigated. The complexes [Ln8(tbzcapc)12(H2O)24]-6(DMF) (Ln = La 1, Ce 2; tbzcapc = 6-[2-N-(l,3,4-thiabiazole)carboxamido]-2-pyridylcarboxylic) show octameric ellipsoid structure. We found the starting ligand btapca had been altered into tbzcapc during the formation process of [Ln8(tbzcapc)12(H2O)24]-6(DMF). The NLO properties of complexes 1 and 2 were investigated via Z-scan techniques. It is interesting that the two isostructural complexes show completely different NLO properties. Complex 1 shows NLO refractive effects without absorption. While complex 2 possesses NLO absorptive behavior without refraction.The reactions of different transition metals with multidentate ligand N,N'-bis(-l,3,4-thiobiazole)-2,6-pyridyldicarboxamide (btapca) afford six new polynuclear complexes: hexanuclear complexes {[Zn6(O)2(btapca)4]-3(DMF>2(H2O)} 3 and {[Zn6(O)2(btapca)4] (DMF) (MeOH) (H2O)}4, pentanuclear complexes{[Zn5(OH)2(btapca)4]4(DMF)-(H2O)} 5, {[Co5(OH)2(btapca)4]-4(DMF) (MeOH) (H2O)}6 and {[Ni5(OH)2(btapca)4]4(DMF) (MeOH)}7, and trinuclear complex {[Fe3(OH)(btapca)3]-2(DMF>2(MeOH)} 8. A dominant characteristic of these polynuclear complexes is that there are u3- or u4-oxygen atoms in the metal polyhedrons. The hexanuclear complexes 3 and 4 show similar octahedral features based on zinc centers. The five metal centers in complexes 5, 6 and 7 arrange in two triangles having one common vertex. While, as for complex 8, three iron(II, III) atoms form a plane with a u3-Oh- in the center. We also report the magnetic properties of complexes 6, 7 and 8. Complex 6 exhibits intramolecular antiferromagnetic exchange, while the analogous complex 7 is dominated byvery strong intramolecular ferromagnetic coupling. The trinuclear complex [Fe3(OH)(btapca)4] 8 shows comparable weak antiferromagnetic coupling.The ligand 2,6-(2-pyridyl) dicarboxamido-pyridine (pdcap) has been synthesized and its coordination properties toward Ag, Zn and Hg in the presence of air have been investigated. The structure of [Ag10(pdcap)4] 5H2O (9) was proven to assume columniform fashion. [Zn4O(pdcap)3] 6H2O (10) consists of three pdcap ligands and four zinc atoms sharing a single oxygen center. In [Hg2(pdcap)2] (11), the two pdcap ligands helically go around the mercury centers with the length of double helix of 3.157A. Multiple competing molecular interactions (metal-ligand, u-stacking and metal-metal) give rise to a range of different molecular architectures. Moreover, we find cluster 9 exhibit very large NLO absorptive and refractive effects, and clusters 10 and 11 only show strong refractive properties. The values are better than the reported cluster compounds.In the Chapter III, a series of metal carboxylate complexes have been synthesized by treating N,N'-dipyridin-2-ylpyridine-2,6-dicarboxamide (H2pdcap),pyridine-2,5-dicarboxylate acid (2,5-H2pda), and phenanthroline (p...
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