Seven Coordination Polymers Derived from Semirigid Tetracarboxylic Acids and N-Donor Ligands: Topological Structures, Unusual Magnetic Properties, and Photoluminescences

Seven new complexes based on H4L1 and H4L2, namely, [Cd-2(L-1)(H2O)(5)](n) (1), {[Cu-5(L-1)(2)(mu(3)-OH)(2)(H2O)(4)]center dot 2H(2)O}(n) (2), {[Cd-2(L-1)-(4,4'-bipy)(2)(H2O)(3)]center dot 2H2O}(n), (3), [Zn-2(L-1)(4,4'-bipy)(H2O)(3)](n) (4), {[Ni-7(L-1)(4)(4,4'-bipy)(12)(H2O)(12)]center dot 2H(2)O} (5), {[Ni-1.5(L-2)(4,4'-bipy)(1.5)(H2O)(4)]center dot H2O}(n) (6), and {[Ni-9(L-2)(6)(dib)(12)(H2O)(18)]center dot 18H(2)O}(n) (7) [(H4L1 = 4-(3',5'-dicarboxylphenoxy)phthalic acid, H4L2 = 3-(3',5'-dicarboxylphenoxy)phthalic acid, 4,4'-bipy = 4,4'-bipyridine, dib = 1,4-di(1H-imidazol-1-yl)benzene], have been synthesized by solvothermal reactions. Complex 1 possesses a 4-connected chiral three-dimensional (3D) structure with a Schlafli symbol of (4.6(3).8(2)). Complex 2 presents a (4,6)-connected porous architecture based on a chair-shaped [Cu-4(mu(3)-OH)(2)](6+) secondary building unit (SBU) with a Schlafli symbol of (4(3).6(3))(2)(4(6).6(6).8(3)), revealing unusual ferromagnetic behavior. Complex 3 exhibits a 2D -> 3D framework through H-bonding interactions, which is a (3,3,4)-connected 2-fold interpenetrated structure with a Schlafli symbol of (6.8(2))(2)(6(3).8(3)). Complex 4 shows a (3,4,6)-connected (4.6(4).8)(2)(6(2).8)(2)(4(2).6(6).8(6).10) topology. Complex 5 displays a rare (3,4)-connected polycatenation structure, possessing identical topologies with a Schlafli symbol of (6(3))(6(5).8) and weakly ferromagnetic behavior. Complex 6 features a (3,4)-connected 3D framework with a Schlafli symbol of (4 x 10(2))(2)(4(2).10(3).12). Complex 7 can be regarded as a (4,4)-connected (6(3).8(3))(2)(8(5).10) topology. Moreover, diverse structural topologies have not been documented hitherto. The magnetic properties of 2 and 5 are discussed in detail. The fluorescence properties have also been analyzed with density functional theory calculations, indicating that the emissions can be ascribed to intraligand charge transfer for 1 and ligand-to-ligand charge transfer for 3-4.