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Two lanthanide MOFs, namely {{Me2NH2}[TbIII(L)]·3H2O·DMF}n (1) and {{Me2NH2}[EuIII(L)]·3H2O·DMF}n (2), based on the flexible ligand 5-(bis(4-carboxybenzyl)amino)isophthalic acid (H4L) have been synthesized under solvothermal conditions, where DMF = N,N-dimethylformamide. The two compounds exhibit a 3D structure with rectangle channels encapsulating [Me2NH2]+ cations. The microporous structure as well as the confinement of cations inside the MOFs pores allows 1 and 2 to act as dual-functional luminescent materials to detect nitroaromatics and metal ions. The experiments show that the luminescence of sample 1 in DMF solution was quenched when the nitrobenzene (NB) content reached 2.3 × 10−2 mol/L and concentration of Fe3+ reached 5 × 10−4 mol/L.

A novel cerium(III) complex, [Ce(Fcterpy)(NO3)3(H2O)]·DEE (1) (DEE = diethylether), bearing the substituted terpyridine ligand 4′-ferrocenyl-2,2′:6′,2″-terpyridine (Fcterpy) has been synthesized and characterized by the single crystal X-ray diffraction technique. Magnetic measurements revealed that complex 1 exhibits a single-ion magnet-like behaviour in the form of field-induced slow magnetic relaxation.

A novel manganese compound with Fe(IV) building block has been synthesized and characterized by single-crystal diffraction analysis, which presents of a 1D staircase chain structure. The adjacent staircase chains are expended into a 2D layer through π-π interaction between the terminal oxalyl groups. Furthermore, the 2D layers are connected to form a 3D supramolecular framework by rich hydrogen bonds. Low-temperature magnetic measurements reveal that intrachain antiferromagnetic couplings dominates through the FeIV-oxamido-MnII pathways, concomitantly with a typical ferrimagnetic behavior.

Three new polyoxometalate-based metal–organic framework compounds [Ag7(3-pttz)4(PMo12O40)]·H2O(1), [Ag6(3-Hpttz)2(3-pttz)2(SiMo12O40)(H2O)2]·2H2O(2) and [Ag6(3-Hpttz)6(PMo12O40)2]·2H2O(3) (3-Hpttz = 5-(3-Pyridyl)-1H-tetrazole) are synthesized hydrothermally by changing the polyoxoanions and the pH values in the same metal–organic system (Ag/pttz), and structurally characterized by IR spectra, elemental analyses and single crystal X-ray diffraction. Compound 1 exhibits a three-dimensional (3D) Ag/3-pttz host framework with larger channels. The discrete [PMo12O40]3− anions, acting as inorganic templates, are embedded in the channels. In compound 2, the Ag/3-pttz motif displays a two-dimensional (2D) stair-like layer, which is linked by [SiMo12O40]4− anions to construct a 3D framework. In compound 3, the Ag/3-pttz motif shows a 1D ribbon-like chain, some of [PMo12O40]3− anions in a “shoulder-to-shoulder” mode link two ribbon-like polymers to form a 1D “quadrangular prism-like” chains, and the others of [PMo12O40]3− anions bond to chains and become pendants of the quadrangular prism, projecting toward two sides. Therefore, compound 3 displays a scarce 1D “quadrangular prism with pendants” structure. In addition, the electrochemical behavior and electrocatalytic activity of compound 1 as an example were investigated.

Reactions of different metal salts with 4-amino-3,5-bis(3-pyridyl)-1,2,4-triazole (3-abpt) gave rise to five new complexes, namely [Cu4(CN)4(3-abpt)2]n (1), [CuBr(3-abpt)]n (2), [CuI(3-abpt)]n (3), [Cu3I3(3-abpt)]n (4) and [Cu(3-abpt)(SO4)(H2O)]n (5). Compounds 1, 3, 4 and 5 are all 2D structures. Compound 1 is a double-layered polymer with an uncommon 3-nodal 3-connected (103)(102.4)4 network, 3 shows a 2D square layered structure, 4 is also a double-layered polymer with 2-nodal 4-connected (3.4.5.62.7)2(3.42.52.7) network and 5 is a 2D structure which is ultimately stacked with an ABAB repeat pattern. Compound 2 is a 1D coordination polymer which exhibits a ladder-like network. The photoluminescence of 1–2 has also been investigated. The long emission lifetimes of 1–2 could be assigned to metal-to-ligand charge transfer triple excited states [MLCT].

Four novel coordination polymers constructed from flexible pamoic acid, namely [Co(pam)(4,4′-bipy)] n · n H 2 O ( 1 ), [Ni(pam)(4,4′-bipy)(H 2 O) 2 ] n ·2 n CH 3 CN ( 2 ), [Cd(pam)(py) 2 ] n · n py ( 3 ) and [Mn 2 (pam) 2 (py) 6 (H 2 O) 2 ] n ·2 n py ( 4 ), (H 2 pam = pamoic acid, 4,4′-bipy = 4,4′-bipyridine, py = pyridine), have been synthesized and characterized by elemental analysis, infrared spectra and X-ray crystallography. Complex 1 is a 2-D coordination polymer constructed from chelating bis-bidentate pam and 4,4′-bipyridine bridging ligands. Complex 2 is a 2-D coordination polymer assembled by bis-monodentate pam and 4,4′-bipyridine, where acetonitrile is filled in the rectangle channels. Both 2-D coordination polymers display undulated (4,4) grid layers as sql topology. Complex 3 displays a 1-D polymeric chain using chelating bis-bidentate pam as bridging ligand. Complex 4 exhibits an interesting bis-monodentate pam-Mn(II) 1-D polymeric chain, in which exist two-type six-coordinated manganese centers. Mn(1) is bound to four pyridine ligands, whereas Mn(2) is combined to two pyridine and two H 2 O molecules. Their thermal stabilities have been investigated. Cadmium complex 3 displays strong green luminescence with emission maximum at 543 nm.

Reactions of metal acetates with 4-amino-3,5-bis(3-pyridyl)-1,2,4-triazole (3-abpt) and co-ligands gave rise to four new complexes, namely [Zn2(3-abpt)(beta)(DMF) (H2O)2]n·nH2O (1), [Zn(3-abpt)(ip)]n·3nH2O (2), [Zn(3-abpt)(ip)(H2O)2]n·2nH2O (3), and [Cu2(3-abpt)2(C6H5COO)4(H2O)2]n·2nH2O (4) (ip = isophthalate, beta = 1,2,4,5-benzenetetracarboxylate). Compound 1 is a 3D coordination polymer with uncommon 3,4-connected (62.8)2(62.82.102) network. Compounds 2–4 are all 1D coordination polymers, which exhibit diversity structures. Compound 2 is a tubular-like chain, 3 is a ring-like network, and 4 is a zigzag chain. Their thermal stabilities and the photoluminescence of 1 have also been investigated.

Three trinuclear zinc(II)/nickel(II) complexes with two pentadentate ligands, N-p-nitrobenzoylsalicylhydrazidate (H-3-p-nbzshz) and N-o-nitrobenzoylsalicylhydrazidate (H-3-o-nbzshz) have been synthesized and characterized by X-ray crystallography. The complex [Zn-3(p-nbzshz)(2)(C5H5N)(4)](n) (1) molecule exhibits a one-dimensional wave-like chain structure resulting from the linkage of phenolate oxygen donor atoms of the ligands between neighboring motifs. The two nickel(II) complexes, Ni-3(p-nbzshz)(2)(C5H5N)(4) (2) and Ni-3(o-nbzshz)(2)(C3H7NO)(2)(C2H6O)(2) (3) are trinuclear complexes in which three nickel(II) centers exhibit alternating square-planar and octahedral geometries. Complex 2 exhibits a curved Ni-3 metal arrangement with a Ni(1)-Ni(2)-Ni(3) angle of 62.36 degrees, while the three nickel atoms in complex 3 are strictly linear with an angle of 180 degrees. (C) 2007 Elsevier Ltd. All rights reserved.

Four copper(I) cyanide coordination polymers containing 2-(n-pyridyl)benzimidazole ligands, namely [Cu2(CN)(2-PyBIm)]n (1), [Cu2(CN)2(3-PyHBIm)]n (2), {[Cu3(CN)3(4-PyHBIm)4] · 2H2O}n (3) and [Cu5(CN)3(4-PyBIm)2]n (4), have been synthesized and characterized by X-ray crystallography. Complex 1 is a one-dimension coordination polymer in which 2-(2-pyridyl)benzimidazole is deprotonated and adopts a bridging tridentate coordination mode. Complex 2 has ladder-like structure in which 2-(3-pyridyl)benzimidazole does not deprotonate and acts as a bidentate bridge. Complex 3 displays a saddle-shaped helical chain constructed through μ2-cyanide group and the outstretched neutral 2-(4-pyridyl)benzimidazole monodentate ligand. Complex 4 shows two-dimension layer polymeric structure in which deprotonated 2-(4-pyridyl)benzimidazole acts as a tridentate bridging ligand. The cyanide groups in four complexes all act as bidentate bridging ligands. These complexes are thermal stable and display luminescence in the solid states.

On the basis of triangular-shaped secondary building units, a hexanuclear manganese(III) complex, [MnIII6O2(sao)6(N3)2(H2O)8]·2.5H2O (1) (H2sao = salicylaldoxime), was synthesized and structurally characterized. The structure of 1 consists of two triangular-shaped [Mn3O] connected with end-to-end (EE) azide group. Magnetic data analysis shows that antiferromagnetic couplings dominated in the complex.

The previously unknown heteropolytungstate (Me4N)10[Fe4(OH)4 (PW10O37)2]·15H2O has been prepared by the reaction of Δ–Na8HPW9O34 and FeCl3 in aqueous solution, and characterized by elemental analysis, infrared spectrum as well as X-ray single crystal structure determination. Four bridging hydroxo groups link with four FeIII ions, forming an eight-member ring; and this Fe4(OH)4 aggregation is sandwiched by two bi-vacant Keggin type heteropolyanion fragments. The bridging hydroxo groups are divided into two classes: one is the hydroxo groups linking two PW10Fe2 half moieties, the other is the hydroxo group linking two FeO6 octahedra in each half moiety. The location of the bridging hydroxo groups is identified by the bond valence sum (BVS) calculations for various oxygen atoms.

Novel cyclic tetranuclear manganese complexes with maleate dianions as bridging ligand, of formula [Mn4(μ-C4H2O4)2(bipy)8](ClO4)4·(MeOH)2(H2O)2 (1) and [Mn4(μ-C4H2O4)2(phen)8](ClO4)4·H2O (2), have been prepared and characterized by elemental analysis, IR spectra, X-ray analysis and magnetic measurements. The crystal structure determination of complex 1 reveals that the cation [Mn4(μ-maleate)2(bipy)8]4+ has a centre of symmetry and the four manganese atoms are bridged by two maleate dianions, forming an unusual 16-membered macrocyclic structure. Each manganese atom is coordinated in cis fashion by two oxygen atoms of bridging maleate ligands and then by four nitrogen atoms from terminal bipyridine ligands, leading to a distorted octahedral geometry. The variable-temperature magnetic properties have been investigated in the range 1.4–300 K. The results show that the magnetic susceptibilities obey the Curie law and no magnetic exchange interaction occurs between the carboxylato-bridged MnII ions.

The one-dimensional manganese(II) complex with 4,4′-bipyridine (4,4′-bipy) as bridging ligand, of formula [Mn(μ-4,4′-bipy)(4,4′-bipy)(NCS) 2 (H 2 O) 2 ] n , has been prepared and characterized by elemental analysis, IR spectra and thermal analysis. Its X-ray crystal structure determination reveals that the local coordination geometry around the Mn II ion is a distorted octahedron. Mn(NCS) 2 (H 2 O) 2 coordination planes are bridged by 4,4′-bipyridines to form an infinite chain structure. A second 4,4′-bipyridine exists in the lattice, linked by hydrogen bonds to coordinated water molecules. The determination of variable-temperature magnetic susceptibilities (74–300 K) shows that the magnetic behaviour obeys the Curie law. There is practically no evidence of any magenitic exchange interaction between the adjacent metal ions.

The first chain copper(I) complex with 4,4′-bipyridine as the bridging ligand, of the formula [μ-4,4′-bipy-Cu(TTA)]n (TTA = 2-thienoyltrifluoroacetone), has been prepared and characterized by elemental analysis, IR and FAB mass spectra. Its X-ray crystal structure determination reveals that the local coordination geometry around copper(I) is a distorted tetrahedron. Cu(TTA) units are bridged by 4,4′-bipyridine to form an infinite zigzag chain with an NCuN angle of 143.3(7)°. The short CuN distance (1.98 A) indicates that quite strong molecular chains have been formed in the crystal.