Seven new metal−organic frameworks (MOFs) [Cu(bib)2(H2O)2](Cl3CCOO)2·2MeOH·2H2O (1), [Cu(bib)2]Cl2·H2O (2), [Cu(bib)2(SO4)(H2O)]·4H2O (3), [Cu(bib)(SO4)(H2O)2] (4), [Cu(bib)(N3)(OAc)]·DMF (5) (OAc = acetate), [Cu(bib)(ox)]·MeOH·2H2O (6) (ox = oxalate), and [Cu(bib)(mal)]·MeOH (7) (mal = malonate) were obtained by reactions of flexible bidentate ligand 1-bromo-3,5-bis(imidazol-1-ylmethyl)benzene (bib) with corresponding copper(II) salts. The structures of these MOFs were established by single-crystal X-ray diffraction analysis. Complexes 1 and 2 have similar one-dimensional (1D) hinged chain structure. Complex 3 has a 2D network structure with (4,4) topology. Complex 4 has M2L2 metallocyclic ring structure and the rings are further linked by the sulfate anions to form a 1D tube-like chain. Complex 5 is also a dinuclear M2L2 metallocyclic ring, which is further connected by Br···Br interactions to form 1D chain. While in the cases of complexes 6 and 7, both have 2D network structure in which the oxalate and malonate anions act as bridging ligands. The results showed that the counteranions play important roles in the construction of MOFs. In addition, the magnetic properties of complexes 6 and 7 were investigated. The results show that weak ferromagnetic interactions occurred between the copper(II) ions linked by the oxalate anions in complex 6, and there is no obvious magnetic interaction between the copper(II) ions bridged by the malonate anions in complex 7.

Three novel copper complexes, [Cu II (titmb)(N 3 ) 2 ]·0.5H 2 O (1), [Cu I 3 (titmb) 2 ](ClO 4 ) 3 (2), and [Cu II (titmb)(SO 4 )]·2.2H 2 O (3), were obtained by reactions of flexible tripodal ligand 1,3,5-tris-(imidazol-1-ylmethyl)-2,4,6-trimethylbenzene (titmb) with the corresponding copper(II) salts using hydrothermal method and their structures were determined by X-ray crystallography. Complex 1 exhibits a one-dimensional (1D) tube-like chain structure, while the 2 possesses a M 3 L 2 molecular cage-like structure, in which the copper atom has a valence of ϩ1, indicating that the Cu II is reduced to Cu I under the hydrothermal condition. Complex 3 has a polycatenated network structure with inclined interpenetration of (6,3) networks. Ligand titmb adopts a cis,cis,cis-conformation in all of the three complexes. The results indicate that the anions play important roles in the structure of the complexes. In addition, complex 2 was further investigated by electrospray massspectrometry.

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A new complex [Pr(bib) 2 (NO 3 ) 3 ] (1) was synthesized by reaction of bidentate imidazole-containing ligand 1-bromo-3,5-bis(imidazol-1-ylmethyl)benzene (bib) with Pr(NO 3 )·6H 2 O and characterized by X-ray crystallography. Complex 1 has a two-dimensional herringbone-like structure with the ligand bib serving as a bridging ligand using its two imidazolyl nitrogen atoms. Ligand bib adopts cis and trans two different conformations, and the Pr(III) atoms are bridged by bib in two different ways. Thermogravimetric analysis for complex 1 was carried out and the result shows that the complex is stable up to 180 • C. Variable-temperature magnetic susceptibility of complex 1 was measured between 1.8 and 300 K and the result shows that the χ M T value decreases continuously over the whole temperature range.

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Assembly of bidentate ligand 1‐(1‐imidazolyl)‐4‐(imidazol‐1‐ylmethyl)benzene (IIMB) with varied metal salts of ZnII, CdII and PbII provide three new complexes, [Zn(IIMB)2](ClO4)2·2H2O (1), [Cd(IIMB)2(SCN)2] (2) and [Pb(IIMB)2(SCN)](SCN) (3). Single crystal X‐ray diffraction studies revealed that complexes 1 and 2 display a similar one‐dimensional double stranded chain structure, while complex 3 is a slight distorted rhombohedral grid network with (4,4) topology. The results indicate that the coordination geometry of the metal ion and the counter anion have great impact on the structure of the complexes. In addition, the photoluminescence properties of ligand IIMB and complexes 1–3 were studied in the solid state at room temperature.

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