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The construction of multifunctional metal-organic frameworks (MOFs) has attracted considerable attention. Two novel Dy-MOFs namely [Dy2(TPTC-2OMe)1.5(H2O)4·H2O]n (1) and {[Dy2(TPTC-2OMe)(H2TPTC-2OMe) (H2O)2]·2H2O}n (2) were obtained by a solvothermal method using 2′,5′-dimethoxy-[1,1′:4′,1″-terphenyl]- 4,4″-dicarboxylic acid (H4TPTC-2OMe) as the ligand. Structure analysis demonstrates that both MOFs 1 and 2 displayed three-dimensional framework structures, in which MOF 1 was with Dy(III) metal chains as nodes, while MOF 2 was with Dy2 binuclear metal clusters as nodes. Interestingly, MOFs 1 and 2 exhibited high thermal and chemistry stabilities and presented relatively high proton conductivity (σ) values of 1.69 × 10-4 S cm-1 and 3.52 × 10-6 S cm-1 at 50 °C and 98% RH. Although there exist a large number of coordinated or free H2O molecules in both structures, it is easier to form an ordered hydrogen-bonding network between the coordinated H2O molecules in the structure of MOFs, resulting in a more excellent proton conductivity of MOF 1. Moreover, MOF 1 exhibited field-induced single-molecule magnet (SMM) behavior with energy barriers (Ueff) of 37.22 K (τ0 = 9.27 × 10-8 s). Furthermore, MOF 1 exhibits obvious second-order nonlinear optical properties. This research provides guidance for the design of novelty multifunctional MOF materials. [ABSTRACT FROM AUTHOR]

A novel CdII-based two-fold interpenetrated metal--organic framework (MOF), namely {[Cd2(BTDB)2(4,4-bpy)]·DMF}n (JXUST-14), (H2BTDB = 4,4'-(benzo[c][1,2,5]thiadiazole-4,7-diyl)dibenzoic acid and 4,4-bpy = 4,4-bipyridine), has been prepared and characterized. Single-crystal structure determination reveals that JXUST-14 has a tetranuclear cluster based 6-connected pcu topological network with Schlafli symbol {412·63}. When soaked in common organic solvents and aqueous solutions with diverse pH values of 2-12 for 48 h, JXUST-14 remains stable. JXUST-14 is a highly selective and sensitive luminescent sensor for L-histidine (His) with a detection limit of 11.1 ppm. JXUST-14 is the first CdII-based MOF for the detection of His via turn-on and fluorescence blue-shift effects. Experimental study and theoretical calculation suggest that the sensing process can be mainly attributed to a charge transfer and energy transfer mechanism. More interestingly, LED lamps of JXUST-14 and JXUST-14@His were successfully developed, which endowed efficient sensitivity for His detection and thus provide great potential for future applications. [ABSTRACT FROM AUTHOR]

Six new coordination polymers (CPs) based on the V-shaped 1,3-bis(benzimidazolyl)benzene (bbib) have been synthesized under solvothermal conditions: [Zn(bbib)(ip)]n (1), {[Zn(bbib)(oba)]·solvents}n (2), {[Zn(bbib)(tp)]·DMF}n (3), [Cd(bbib)(ip)]n (4), {[Cd(bbib)(oba)]·H2O·solvents}n (5) and {[Cd(bbib)(tp)]·DMF}n (6) (ip = isophthalate, oba = 4,4′-oxybisbenzoate and tp = terephthalate). Complexes 1-3 display a plane minimal net, (4,4) sheet and a hexagonal plane net, respectively. The structures of 4-6 range from a 1D zigzag chain (4), 2D (4,4) sheet (5) to a 3D "pillar-layer" coordination framework with pcu α-Po topology (6). The structural transition from 1D to 3D among these complexes is realized with the aid of different auxiliary ligands. The results demonstrate that the conformations and coordination modes of dicarboxylate ligands make an impact on the structural diversity of ZnII/CdII coordination polymers. To the best of our knowledge, the CPs based on the bbib ligand have been successfully prepared for the first time. Moreover, complex 2 is a good bifunctional chemosensor for the detection of both Fe3+ and MnO4 - with the detection limits of 3.31 ppm and 8.81 ppm, respectively, indicating that 2 could be used as an efficient fluorescent sensor with high sensitivity and selectivity for Fe3+ and MnO4-. [ABSTRACT FROM AUTHOR]

Two couples of enantiomedcally pure chiral cyano-bridged heterobimetallic chain coordination polymers, [Mn((R,R)Salcy)Fe(Tp)(CN)3∙H2O∙1/2CH3CN]n (1), [Mn((S,S)-Salcy)Fe(Tp)(CN)3∙H2O—1/2CH3CN]n (2), [Mn((R,R)Salcy)Fe(bpca)(CN)3—H2O]n (3), and [Mn((S,-Salcy)Fe(bpca)(CN)3∙H2O]n (4) [(R,R)-Salcy or (S,S)-Salcy = (R,R)- or (S,S)-N,N'-(1,2-cyclohexanediylethylene)bis(salicylideneiminato) dianion, Tp = tris(pyrazofyl)hydroborate, bpca = bis(2-pyddylcarbonyl)amidate anion], were synthesized using the mod8ied cyanometalate building blocks [Fe(L)(CN)3]- (L = Tp, bpca) and the chiral polydentate Schiff base manganese(lll) complex fragments. The circular dictiroism measurements showed Cotton effects of the opposite sign at the same wavelength for each pair of enantiomers. Magnetic property studies indicated that complexes 1 and 2 show not only intrachain but also interchain field-induced metamagnetic transitions from an antiferromagnetic to a ferromagnetic state and exhibit an antiferromagnetic tong-range ordering with a TN of 3.2 K, while enantiomers 3 and 4 are typical antiferromagnetic coupling compounds. Furthermore, complex 3 exhibits a ferroetectric behavior that relates to the polar point group C2, in which it crystallizes. [ABSTRACT FROM AUTHOR]