| The complexes constructed by azaaromatic polycarboxylate ligands have received considerable attention becourse of their intriguing variety of architectures, host–guest chemistry, electrical conductivity, catalysis, magnetism and optical applications, which have been the very significative research orientation in the material science and supramolecular chemistry. This thesis reviewed the representative aromatic tricarboxylate complexes: benzene-1,3,5-tricarboxylate and pyridine–2,4,6–tricarboxylate complexes which have been reported according to their structure types from zero–dimensional to three–dimensianal, and then discussed the relevant characters, the applications in magnetism, luminescence, and the synthesis strategies of pyridine–2,4,6–tricarboxylate complexes. Then the 14 complexes based on pyridine–2,4,6–tricarboxylate transition metals and lanthanides, [Mn3(H2O)8(ptc)2]·4H2O (1),Na[Co3(H2O)2(ptc)3]·H2O (2),Na0.5[(Zn3O)(H2O)(ptc)1.5] (3),K2[Ni(Hptc)2](H3ptc)2·4.25H2O (4),Ni(phen)(H2O)(Hptc) (5),[Ni(bpy)2(H2O)2][Ni(Hptc)2]·6H2O (6),[Ni(phen)(H2O)(H2ptc)]OH·3H2O (7),[Co(2,2′–bpy)2(2,4–Hpdc)](ClO4)2·3H2O (8),[Ln(H2O)3(ptc)]·H2O (Ln = Tb (9), Pr (10)),[Ln2(H2O)9(ptc)2]·3H2O (Ln = Tb (11), Dy (12), Yb (13), Lu (14)) (H3ptc = pyridine–2,4,6–tricarboxylic acid; phen = 1,10–phenanthroline; bpy = 2,2'–bipyridine), and their X-ray single crystal diffraction, X-ray powder diffraction, IR spectra, TG-DTA analyses, variable–tempreture magnetic susceptibility analyses and luminescence behavior were also demonstrated.1-3 are assembled by ptc3– and transition metal and exhibited various structure styles. 1 contains 2D layers which connected by extensive H-bonding interactions into 3D supramolecular frameworks. Three Co(Ⅱ) cations and O from ptc3– constitute [Co(ptc)2/2] in 2, which accommodate the Na+ ions, and thus lead into 3D supramolecular architecture. 3 contains the olivary cage unit which linked each other end to end to generate 1D chains. The resulting chains are futher bridged into 3D frameworks.The self–assembly of transition metal salt, pyridine–2,4,6–tricarboxylic acid and 1,10–phenanthroline or 2,2'–bipyridine result in the formation of comlexs 4–8. Compound 4–6 are constituted by hydrogen pyridine–2,4,6–tricarboxylate dianion Hptc2– and Ni(Ⅱ) cations which contain [Ni(Hptc)2]– or [Ni(Hptc)2] units, engaging in hydrogen-bond andπ–πstacking interactions to form 3D network. Complex 7 is assembled by dihydrogen pyridine–2,4,6–tricarboxylate anion H2ptc– and Ni(Ⅱ) through changing the pH value with NaOH. There is in suit ligand syntheses in compoud 8, the 6–carboxyl of pyridine–2,4,6–tricarboxylic acid is broken down, engendering pyridine–2,4–dicarboxylic acid coordinated with Co(Ⅲ) cations, 3D supramolecular frameworks are formed through hydrogen bond among [Co(2,2′–bpy)2(2,4–Hpdc)]+ units.9–14 are assembled by ptc3– and lanthanides. 9 and 10 are isomorphism complexes which bridged by the 4,4′–bicapped trigonal prismatically coordinated Tb(Ⅲ) or Pr(Ⅲ) cations and ptc3– anions in aμ3η6 coordination mode to generate 2D layers of (4·82) topological net. Isomorphism complexes 11–14 are bridged byπ–πstacking interactions from [Ln4(ptc)4] units to generate 2D layers parallel to (100), 1D hydrogen-bond clusters chains T4(1)6(1) among layers making a contribution to satabilization of 3D supramolecular frameworks. The UV/Vis spectra and fluorescent properties in 10–14 can be assigned to ligand to lanthanide ions transitions. Magnetic properties in the temperature range 2.0–300 K shows the occurrence of weak antiferromagnetic interactions between the Ln(Ⅲ) ions of 10–13.
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