| Six compounds (1～6) were synthesized by hydrothermal reaction, using terephthalic acid (H2bdc), phthalic acid (H2phth) as the first ligand and the bidentate chelating ligands 1, 10-phenanthroline(phen) or 2, 2'-bipyridine (2, 2'-bipy) and bridging ligand 4, 4'-bipyridine (4, 4'-bipy) as the second ligand. [Zn(2, 2'-bipy)(H2O)(phth)]2 (1), [Zn(2,2'-bipy)(H2O)(phth)]2·2H2O (2), [Cd(2, 2'-bipy)(H2O)2(phth)]n (3) are d10 metals compounds containing phth ligand. [CaZn4(μ3-OH)2(2,2'-bipy)2(bdc)4] (4), [CaZn4-(μ3-OH)2(phen)2(bdc)4] (5), [CaZn2(4, 4'-bipy)(bdc)3] (6) are alkaline earth-transition heterometal complexes. All the compounds were characterized by the IR and element analyses. The crystal structures of these compounds were determined by X-ray single crystal diffraction method. Futhermore, the thermal stability was analysized by the TG and DSC, and the fluorescent properties were studied for compounds 1, 2,4, 5. The main results are as following:1. Compounds 1, 3, 4, 5, 6 are crystallized in triclinic crystal system and P-1 space group. Compound 2 is monoclinic crystal system, and P2(1)/n space group.2. The central metal atom Zn(II) in compounds 1, 2, 4, 5, 6 has a distored tetrahedron(l, 4, 5, 6), distorted square pyramidal(4, 5) and distorted octahedronal(2) coordination geometry, respectively; Cd(II) in 3 is six coordinated and a distorted octahedron coordination geometry. The coordination modes of dicarboxylic acid ligands within these compounds are diverse, including monodentate, bridging bidentate, chelating bidentate, chelating and monodentate double bridging as well. Due to the multi-coordination mode of diacid ligands, the structures of these compounds are different and various. The compounds 1, 2 are binuclear complex through phth different bridge modes. The compounds 3 hold 1D chain through phth monodentate bridging. Compounds 4, 5, 6 have eight-connected 3D network structure.3. The results of thermal analyses for the compounds show that all compounds lose crystallized H2O firstly, and then CO or CO2 were released. The decomposition temperatures of the coordination ligands phen and 2, 2'-bipy range from 140 to 500℃. Compounds 1, 4 begin to decompose more completely at the relatively lower temperatures. The others are more standable relatively.4. The compounds 1, 2, 4, 5 at the solid state show fluorescent emission bands around 515 nm, 550 nm, 531 nm and 482 nm, resectively, under 330～370 nm light excitation. The intensity and location of emission spectra are influence by the kind of ligand and the structure of compands. The result means that the compounds are potential solid luminescent material.
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