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Two new 3d-3d homo-and heterometallic coordination polymers with mixed organic ligands, namely, 2) [HIBC = 3,5-di(1H-imidazol-1-yl)benzoic acid, H 3 BTC = 1,3,5-benzenetricarboxylic acid], have been synthesized and fully characterized by X-ray diffraction, IR, elemental analysis, thermogravimetric analysis, photoluminescence, and magnetic measurements. Complex 1 with homonuclear Zn(II) is a rare threedimensional (3D) (3,6)-connected rtl (rutile) framework with [Zn 2 O 2 ] and [Zn 2 (OCO) 2 ] two different kinds of binuclear Zn(II) secondary building units (SBUs). While complex 2 with heteronuclear Cd(II) and Co(II) atoms is a 3D framework based on [Cd 2 O 2 ] and [Co 2 O 2 ] SBUs. In 2, the SBUs are extended into an infinite eight-connected rare hex-type (hexagonal-type) network. The binuclear [Co 2 O 2 ] SBU in 2 shows antiferromagnetic interactions. Both 1 and 2 were constructed by the same ligands, however with completely different structures and topologies, the results revealed that the coordination geometries of the metal centers have a subtle influence on the structure of the complexes.

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Seven new coordination polymers {[Cu3(tib)4](NO3)6·4.94H2O} n (1), {[Cu2(tib)2(SO4)2]·2EtOH·2H2O} n (2), [Cu(tib)Cl2] n (3), {[Cd(tib)2](NO3)2·4H2O} n (4), {[Cd(tib)(H2O)2(SO4)]·EtOH·H2O} n (5) {[Co(tib)(H2O)2(SO4)]·EtOH·H2O} n (6), and {[Ni(tib)(H2O)2(SO4)]·EtOH·H2O} n (7) (EtOH = ethanol) were prepared by reactions of flexible tripodal ligand 1,3,5-tris(imidazol-1-ylmethyl)benzene (tib) with the corresponding metal salts. Their structures were determined by X-ray crystallography. The different structures of 1−3 as well as 4 and 5 indicate that the counteranions play an important role in the construction of coordination polymers. The distinct structures of Cu(II) and Cd(II) complexes with the same counteranion demonstrate that the metal centers with different coordination geometry have a significant influence on the structures. The same 1D chain structure of 5−7 indicated that the metal centers with the same octahedral coordination geometry do not affect the structure of the complexes. On the other hand, ligand tib acts as a three-connecting linker to connect three M(II) centers with different conformations. In 1, two different conformations (cis, trans, trans -, and trans -) of tib coexist. In 2−4, tib adopts the cis, trans, trans-conformation, while in the case of 5−7, tib has the cis, cis, cis-conformation. The results attest that the flexible tripodal ligand tib can adopt different conformations to form complexes with varied structures. Furthermore, the reversible anion exchange properties of 1 and 4 were studied.

Nine new coordination polymers [Mn(L)(OX)] (1), [Zn(L)(MBDC)] (2), [Zn(L)(BPDA)] (3), 7), [Co(L)(e,e-trans-1,4-CHDC)]$2H 2 O (8) and [Co(L)(e,e,e-cis-1,3,5-HCHTC)]$0.45H 2 O (9) were obtained by reactions of varied metal salts with 1,4-di(1H-imidazol-4-yl) benzene (L) in the presence of corresponding auxiliary ligands of oxalic acid (H 2 OX), 5-methyl-1,3benzenedicarboxylic acid (H 2 MBDC), 4,4 0 -biphenyldicarboxylic acid (H 2 BPDA), benzene-1,3,5triacetic acid (H 3 BTA), 1,2,4,5-benzenetetracarboxylic acid (H 4 BTCA), cis-1,2cyclohexanedicarboxylic acid (cis-1,2-H 2 CHDC), cis-/trans-1,4-cyclohexanedicarboxylic acid (cis-/ trans-1,4-H 2 CHDC) and cis-1,3,5-cyclohexane tricarboxylic acid (cis-1,3,5-H 3 CHTC), respectively. Complex 1 has a one-dimensional (1D) chain structure and 2 has a two-dimensional (2D) network with 6 3 -hcb topology. Complex 3 is a complicated uninodal 4-connected three-dimensional (3D) net with Point (Schl€ afli

Six new metal–organic coordination polymers [Mn­(H3L)­(ox)]·H2O (1), [Zn2(H2L)­(pbdc)­(μ2-OH)]·2H2O (2), [Co­(H3L)­(obea)]·3H2O (3), [Ni­(H3L)­(pbea)] (4), [Co­(H3L)­(pbea)­(H2O)2] (5), and [Co4(H2L)2(pbea)3] (6) were synthesized by reactions of the corresponding metal salt with rigid tripodal ligand 1,3,5-tri­(1H-imidazol-4-yl)­benzene (H3L) and different dicarboxylic acid of oxalic acid (H2ox), 1,4-benzenedicarboxylic acid (H2pbdc), 1,2-phenylenediacetic acid (H2obea), 1,4-phenylenediacetic acid (H2pbea), respectively. The results of X-ray crystallographic analysis indicate that 1 and 3 are two-dimensional (2D) networks with 63-hcb topology, while 2 is (4,5)-connected three-dimensional (3D) net with Point (Schläfli) symbol of (42·52·72)­(42·53·74·8). Complex 4 is a binodal (3,4)-connected 2D network with V 2 O 5 -type topology. Complexes 5 and 6 were obtained through controlling reaction temperature, 5 features a one-dimensional (1D) chain, whereas 6 is an unprecedented tetra-nodal (3,4)-connected 3D net with Point (Schläfli) symbol of (4·62·103)­(4·62)­(4·64·8)2 attributable to the rich coordination modes of the ligands. The results of magnetic measurements showed that there are antiferromagnetic interactions in 1. Complex 2 exhibits intense light blue emission in the solid state at room temperature, while 3 shows water vapor adsorption property.