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Two novel complexes, {[Cd 3 (L) 2 (H 2 O) 2 ]·(H 2 O) 4 } n (1) and {[Mn(HL)(H 2 O) 2 ]·(H 2 O)} n (2), which are synthesized by the reaction of 3-(2, 4-dicarboxyphenyl)-4-carboxypyridine ligand with cadmium and manganese metal ions under the solvothermal method. The complex 1 is a 3D framework based upon trinuclear [Cd 3 (μ 2 -COO) 4 (μ 1 -COO) 4 (N) 2 ] SBUs, and the complex 2 is a one-dimensional metal oxygen chain based upon binuclear [Mn 2 (μ 2 -COO) 2 (μ 1 -COO) 2 (N) 2 ] SBUs. The solid fluorescence analysis of complex 1 reveals that the emission peak of 451 nm when its excitation peak is 336 nm. The fluorescence detection experiments of complex 1 showed that Fe3+, Cr 2 O 7 2− and CrO 4 2− can effectively to be detected. Furthermore, their limits of detection are 1.47 × 10−3 M, 1.31 × 10−3 M and 1.25 × 10−3 M, respectively. It has good recovery properties as a potential multifunctional fluorescence sensor. Besides, the quenching mechanism of fluorescence sensing is also discussed. In addition, the magnetic studies of complex 2 show strong antiferromagnetic interactions between its neighboring Mn(II) ions. [Display omitted] • Two novel stable complexes were constructed based on particular trinuclear and binuclear metal clusters. • Complex 1 shows high selectivity and sensitivity to detect Fe3+, Cr 2 O 7 2− and CrO 4 2− ions with low detection limit. • Complex 2 possesses antiferromagnetic interaction between its Mn (II) ions. [ABSTRACT FROM AUTHOR]

By employing the ligand 2-(isonicotinamido)terephthalic acid (H 2 L) containing the amide functional groups, a Cd-MOF, {[Cd 2 L 2 (H 2 O) 2 ]·4H 2 O} n (1) has been constructed by solvothermal synthesis. The dinuclear clusters [Cd 2 (COO) 2 ] in 1 are linked by the pyridinyl and carboxylate groups of ligands to form a three-dimensional (3D) skeleton, containing 1D channels with the free amide groups. The activated framework shows good stability in water and high selectivity for CO 2 over CH 4. The open Cd2+ site as Lewis acidic center makes the MOF achieve efficiently catalytic conversion for CO 2 cycloaddition with epoxides. Furthermore, 1 also exhibits good chemical stability in water, allowing the detection for ronidazole (RDZ) and dimetridazole (DTZ) with the low detection limit and rapid response. A Cd-MOF with excellent stability in water and strong fluorescence has been constructed by a pyridyl-carboxyl ligand with amide groups, which reveals high adsorption selectivity for CO 2 over CH 4 , efficiently catalytic conversion of CO 2 and epoxides, and selective fluorescence sensing for ronidazole (RDZ) and dimetridazole (DTZ) in water. Image 1 • A stable-water porous Cd(II)-MOF containing open metal ion sites was synthesized. • MOF shows efficiently catalytic conversion for the CO 2 cycloaddition with epoxides. • MOF shows sensitive fluorescent sensing for ronidazole and dimetridazole in water. [ABSTRACT FROM AUTHOR]

A series of new alkaline earth-metal organic frameworks (AE-MOFs), i.e. {[Mg 2 (μ 6 -L)(μ 2 -OH 2)(H 2 O) 4 ]·DMF} n (1), [Ca 2 (μ 10 -L)(EtOH)] n (2), [Sr(μ 6 -H 2 L)(MeOH)] n (3) and {[Ba 1.5 (μ 5 -H 2 L)(μ 4 -H 3 L)(H 2 O) 3 ]·2(H 2 O)} n (4) were synthesized under solvothermal reaction by employing a symmetrical V-shaped multicarboxylic acid ligand H 4 L (H 4 L = 5,5′-oxydiisophthalic acid), resulting in versatile coordination modes as well as various topologies. 1 forms a uninodal 4-connected (66)- dia 3D topology based on dinuclear Mg 2 (COO) 2 (μ 2 -OH 2) clusters. 2 displays an unprecedented 3-nodal (5,5,10)-connected 3D net with (424·621)(48·62) 2 topology based on 1D [Ca(COO)] n chains and dinuclear Ca 2 (COO) 2 clusters. 3 indicates a uninodal 6-connected 3D net with (410·65)- sma topology based on 1D [Sr(COO)] n chains. 4 features a new 4-nodal (4,5,6,6)-connected net with (43·63) 2 (46·64) 2 (46·68·8)(46·69) 2 topology based on two types of 1D chains. 1-4 show solid-state fluorescent properties at ambient temperature. Especially, 1 and 2 have multiresponsive recognition of Fe3+ and Pb2+ ions, Fe3+ and Cu2+ ions, respectively, while 3 and 4 show single selective detection for Fe3+ ion, signifying that they could be potential fluorescent sensors for specific heavy metal ions in water system. The sensing mechanism has also been discussed in detail. Structural diversity in four AE-MOFs caused by rich coordination modes of a V-shaped multicarboxylic acid ligand have been observed, revealing solid-state fluorescent properties and fluorescent sensors for heavy metal ions (Fe3+, Pb2+ and Cu2+). Image 1 • Four alkaline earth metal MOFs were constructed by a tetracarboxylic acid ligand. • The ligand shows versatile coordination modes and leads to various topologies. • The MOFs reveal selective fluorescent sensors for specific heavy metal ions. [ABSTRACT FROM AUTHOR]

A new porous metal-organic framework, namely [Co 3 (L)(OH) 2 (H 2 O) 4 ]·NMP·3H 2 O (1), has been yielded by using Co(II) and rigid V-shaped 2,6-di(2′,5′-dicarboxylphenyl)pyridine (H 4 L). The structure analysis revealed that MOF 1 is a three-dimensional (3D) porous framework with 1D [Co 3 (OH) 2 ] n ferromagnetic chains. The gas sorption measurements and the IAST analysis indicated MOF 1 has a relatively high selectivity for C 2 H 6 and CO 2 over CH 4. The magnetic properties indicated that MOF 1 has the ferrimagnetic and slow magnetic relaxation behavior, giving an interesting single-chain magnet behavior with an effective energy barrier of 15.82 K. A new 3D porous MOF 1 has been successfully synthesized. Gas sorption tests showed that MOF 1 has a relatively high adsorption capacity and selectivity for C 2 H 6 and CO 2 over CH 4. And also, MOF 1 displays the ferrimagnetic and slow magnetic relaxation behavior, giving an interesting single-chain magnet with an effective energy barrier of 15.82 K. Image 1 • The rigid V-shaped nitrogen heterocyclic carboxylic acid ligand 2,6-di(2′,5′-dicarboxylphenyl)pyridine(H 4 L) and Co(II) ions was selected as the building units to build porous crystalline MOF. • Structure analysis revealed that MOF 1 is a three-dimensional (3D) porous framework with 1D [Co 3 (OH) 2 ] n ferromagnetic chains. • Gas sorption measurements and the IAST analysis showed that MOF 1 has the higher adsorption selectivity for C 2 H 6 and CO 2 over CH 4. • Magnetic properties indicated that MOF 1 has the ferrimagnetic and slow magnetic relaxation behavior. [ABSTRACT FROM AUTHOR]

Two new 2D MOFs, namely, {[Cd 2 (HL)(H 2 O)(DMF) 2 ]·(H 2 O)·(DMF)} n (1), {[Co 2 (HL)(H 2 O)(DMF) 2 ]·(H 2 O)·(DMF)} n (2) were constructed under the solvothermal conditions by using 2,4-di(2′,5′-dicarboxylphenyl)benzoic acid and d10 metal ion Cd(Ⅱ) and Co(Ⅱ). Because the diversity of ligands leads to two different coordination patterns in complexes 1–2 , resulting in 1 and 2 with multiple structures. Both 1 and 2 exhibit a 3D supramolecular framework, which based on different metal-oxygen chains. The chains form a 2D layered structure through the carboxyl oxygen atoms in the ligand. The solid-state luminescence spectra of 1 at room temperature showed that the maximum emission peak is 458 nm (λex = 346 nm). At the same time, 1 showed high fluorescence selectivity and low detection limit for Fe3+ cations, Cr 2 O 7 2− and CrO 4 2− anions in aqueous solution, and can be used as a potential multifunctional material for the detection of these substances. In addition, the fluorescence sensing properties and quenching mechanism of the above ions are discussed in detail. [Display omitted] • Two novel 2D MOFs were constructed based on a V-shaped rigid pentacarboxylic acid ligand. • Complexes 1 and 2 feature 2D frameworks based on diverse metal-oxygen chains with high open metal sites. • 1 shows high selectivity and sensitivity to detect Fe3+, Cr 2 O 7 2− and CrO 4 2− ions with low detection limit. • The fluorescence quenching mechanism of complex 1 was described in detail. [ABSTRACT FROM AUTHOR]

Abstract To synthesize novel polynuclear lanthanide single-molecule magnets, a tetranuclear dysprosium compound, namely [Dy 4 (L) 4 (OH) 2 (DMF) 2 (TMAA) 2 ] •2 (CH 3 CN) (H 2 L = 2-(2-Hydroxy-3-methoxybenzylideneamino)phenol, HTMAA = trimethylacetic acid, DMF = dimethylformamide, and CH 3 CN = acetonitrile), was synthesized, structurally and magnetically characterized. The key structural feature of this compound is that four Dy(III) ions are nearly coplanar in a regular parallelogram, forming a distorted defective dicubane {Dy 4 O 8 } core. Furthermore, this compound shows Single Molecule Magnets (SMMs) behaviour with a high energy barrier of 56 K among tetranuclear Dy(III) SMMs. Graphical abstract A novel tetranuclear dysprosium compound, [Dy 4 (L) 4 (OH) 2 (DMF) 2 (TMAA) 2 ] •2 (CH 3 CN) (H 2 L = 2-(2-Hydroxy-3-methoxybenzylideneamino)phenol, HTMAA = trimethylacetic acid), was synthesized, structurally and magnetically characterized. Magnetic susceptibilities to an alternating current revealed that the compound exhibits single molecule magnet behaviour. Image 1 Highlights • A novel tetranuclear dysprosium compound, [Dy 4 (L) 4 (OH) 2 (DMF) 2 (TMAA) 2 ] •2 (CH 3 CN), was synthesized, structurally and magnetically characterized. • The key structural feature of this compound is that four Dy(III) ions are nearly coplanar in a regular parallelogram, forming a dicubane {Dy 4 O 8 } core. • AC magnetic susceptibilities revealed that the compound exhibits single molecule magnet behaviour with a high energy barrier of 56 K. [ABSTRACT FROM AUTHOR]

Abstract In order to explore the metal ions-controlled syntheses of coordination polymers (CPs), the temperature and solvent ratio were fixed in the reaction processes. By selecting a series of s- and d-block metal ions, five new CPs, [ZnL 0.5 (H 2 O) 2 ] n (1), [CoL 0.5 (H 2 O) 2 ] n (2), [Mn(H 2 L)(H 2 O) 2 ] n (3), [Ca(H 2 L)(H 2 O) 2 ] n (4) and [Ba(H 2 L)(H 2 O) 2 ] n (5), have been synthesized by employing a less-investigated oxalamide N,N′ -bis(4-phthalic acid) (H 4 L) ligand. H 4 L shows very versatile coordination modes and leads to various frameworks, including isomorphous 2D grid-like layer based on M 2 O 2 cores for 1 and 2 , isomorphous 4-connected 3D PtS frameworks based on 1D [M(CO 2) 2 ] n chains for 3 and 4 , and a 2D wave - like layer based on [BaO 3 ] n chains for 5. 2 and 3 reveal the antiferromagnetic and ferromagnetic properties, respectively, while 1 , 4 and 5 possesses strong solid state luminescence. Graphical abstract Five new CPs with magnetic properties and luminescence have been constructed based on s- and d-block metals, and the oxalamide N,N′ -bis(4-phthalic acid) ligand displays versatile coordination modes and various architectures. fx1 Highlights • Five CPs were constructed by an oxalamide N,N′ -bis(4-phthalic acid) ligand. • The versatile coordinated modes of ligands lead to various architectures of CPs. • Antiferromagnetic and ferromagnetic properties as well as luminescence were found. [ABSTRACT FROM AUTHOR]

Abstract We study adsorption behaviors of isomorphic metal-doped metal-organic frameworks in the field of dyeing wastewater treatment technology. Herein, a series of 3D isostructural Co2+/Cd2+ metal-doped metal-organic frameworks named compounds 1 – 5 were successfully synthesized under hydrothermal conditions and used in adsorbing and separation dyes. We demonstrate that dye molecules can be adsorbed on the external surface of the MOFs and their loadings can be tuned by adjusting the rate of the central metal atoms. We show that compound 5 crystals containing Cd2+ are selective adsorbent for pH, temperature, ionic strength responsive adsorption. Their adsorptive properties of cationic dyes in aqueous solutions are higher than that of neutral and anionic dyes. Our method of isomorphic metal-doped opens new possibilities to construct adsorption strength regulation systems for a wide range of applications and facilitates new efforts in environmental purification. Graphical abstract fx1 Highlights • Study on the effect of metal ions on the adsorption of dyes by isomorphic metal doping. We characterize the synthesized compounds, which adsorb a series of dyes (cationic, neutral and anionic dyes). • Some typical organic dyes such as Methylene Blue(MB), Methyl Violet(MV), Phenol Red(PR), Methyl Orange(MO) and Congo Red(CR) were selected as targeted models. For compounds 1 – 5 doped with different contents of metal, the adsorption amount of MV increased with the increasing content of Cd2+ which is in the frameworks. The compound 5 has maximum adsorption amount which can reach 5.93 mg g−1. • Compounds 1-5 have the adsorption capacity for cationic dyes, and the adsorption capacity for MV is better than MB. Compound 5 almost don't carry the neutral dye PR, while compound 5 hardly adsorb anionic dye, such as MO and CR. • We study many factors (pH, temperature, ionic strength)of the adsorption of dye on the compound 5. The experiment shows that the increase of temperature is beneficial to the adsorption in a specific range and the dye adsorption is better under alkaline conditions. • Compound 5 successfully adsorbed MV and MB from mixed dyes with removal percentages of 80% and 90%, respectively. it is stable in the solvent environment. The recyclability of compound 5 adsorbed MV which was investigated over five cycles, the fluctuation of the adsorption capacity was less than 5%. Perform correlation calculations between adsorption kinetics and thermodynamics. [ABSTRACT FROM AUTHOR]

Abstract Four new water-stable luminescent metal-organic frameworks (MOFs), namely {[Zn 4 (L) 2 (H 2 O) 4 (OH) 2 ]·3NMP} n (1), {[Zn 3 (L) 2 (H 2 O) 2 ]·Diox} n (2), {[Cd 3 (L) 2 (H 2 O) 5 ]·NMP·3H 2 O} n (3), and {[Pb 3 (L) 2 (NMP) 2 (H 2 O)]·H 2 O} n (4), (H 3 L = 5-(1-(carboxymethyl)pyrazol-3-yl)isophthalic acid; NMP = N-methyl-2-Pyrrolidoneand; Diox = 1,4-Dioxane) have been solvothermally synthesized with different solvents. The single crystal structures of 1 – 4 reveal that complexes 1 and 2 form the 2D (3,6)-connected kgd nets based on the tetranuclear [Zn 4 (μ 1 -COO) 2 (μ 2 -COO) 4 ] clusters and trinuclear [Zn 3 (μ 1 -COO) 2 (μ 2 -COO) 4 ] clusters, respectively. Complex 3 displays a 2D (3,6)-connected kgd net based on the trinuclear [Cd 3 (μ 1 -COO) 4 (μ 2 -COO) 2 ] clusters. Complex 4 presents a 2D layer with a rod-shaped SBUs. The solid-state luminescence properties and water stability of these complexes were investigated carefully, showing that 1 displays high selectivity for Fe3+, CrO 4 2−, and Cr 2 O 7 2− via luminescence quenching effects with low detection limits. The probable quenching mechanisms have been studied in detail. Graphical abstract Four new water-stable luminescent metal-organic frameworks (MOFs) have been solvothermally synthesized via 5-(1-(carboxymethyl)pyrazol-3-yl)isophthalic acid ligand in different solvents. The single crystal structures of 1 - 4 reveal that complexes 1 and 2 form the 2D (3,6)-connected kgd nets based on the tetranuclear [Zn 4 (μ 1 -COO) 2 (μ 2 -COO) 4 ] clusters and trinuclear [Zn 3 (μ 1 -COO) 2 (μ 2 -COO) 4 ] clusters, respectively. Complex 3 displays a 2D (3,6)-connected kgd net based on the trinuclear [Cd 3 (μ 1 -COO) 4 (μ 2 -COO) 2 ] clusters. Complex 4 presents a 2D layer with a rod-shaped SBUs. The solid-state luminescence properties and water stability of these complexes were investigated carefully, showing that 1 displays high selectivity for Fe3+, CrO 4 2−, and Cr 2 O 7 2− via luminescence quenching effects with low detection limits. The probable quenching mechanisms have been studied in detail. fx1 Highlights • Four new Zn/Cd/Pb luminescent metal-organic frameworks have been synthesized and structurally characterized. • The water-stable of complexes 1-4 have been researched. • Compound 1 shows highly selective and sensitive response to Fe3+, CrO 4 2- and Cr 2 O 7 2-. [ABSTRACT FROM AUTHOR]

A systematic study has been conducted on a novel luminescent metal-organic framework, {[Zn(bpyp)( L -OH)]·DMF·2H 2 O} n ( 1 ), to explore its sensing mechanisms to Fe 3+ . Structure analyses show that compound 1 exist pyridine N atoms and -OH groups on the pore surface for specific sensing of metal ions via Lewis acid-base interactions. On this consideration, the quenching mechanisms are studied and the processes are controlled by multiple mechanisms in which dynamic and static mechanisms are calculated, achieving the quantification evaluation of the quenching process. This work not only achieves the quantitative evaluation of the luminescence quenching but also provides certain insights into the quenching process, and the possible mechanisms explored in this work may inspire future research and design of target luminescent metal-organic frameworks (LMOFs) with specific functions. [ABSTRACT FROM AUTHOR]

Two new Co(II) metal-organic frameworks, namely [Co 2 (bpm)(H 2 O) 3 (L)] n ( 1 ) and {[Co(bpe)(H 2 O)(H 2 L)]·(bpe) 0.5 ·(H 2 O)} n ( 2 ), (H 4 L=1,1′:2′,1″-terphenyl-3,3″,4′,5′-tetracarboxylic acid, bpm=bis(4-pyridyl)amine, bpe=1,2-bis(4-pyridyl)ethene), have been obtained under hydrothermal conditions. Both complexes 1 and 2 have been characterized by elemental analysis, IR spectra, single-crystal X-ray diffraction, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA). Complexes 1 and 2 consist of 1D Co(II) chains bridging by carboxylate groups in syn-anti fashion. 1 shows a novel 3D tri-nodal (4,6,10)-connected net with a (3.4 3 .5 2 ) 2 (3 2 .4 14 .5 12 .6 12 .7 4 .8)(3 2 .4 2 .5 5 .6 4 .7 2 ) topology. While 2 exhibits a 2D sql layer. Magnetic susceptibility measurements indicate that both 1 and 2 show weak antiferromagnetic interactions between the adjacent Co(II) ions in 300–8 K for 1 and 300–16 K for 2 , respectively, and then 2 also displays ferromagnetic coupling at lower temperatures. [ABSTRACT FROM AUTHOR]

Three 2D luminescent coordination polymers with helical frameworks, [ZnL 2 ] n ( 1 ) and {[ M L 2 ]·(H 2 O)} n ( M =Zn ( 2 ), Cd ( 3 )) (HL=4-((2-methyl-1 H -imidazol-1-yl)methyl)benzoic acid), have been assembled under hydro(solvo)thermal conditions. Complex 1 is in chiral space group and displays a rare 2D→2D 2-fold parallel interpenetrated layer network with two types of chiral double helixes. Interestingly, the single crystal structure analyses indicate the coexistence of enantiomers la and 1b in one pot, while the bulk crystallization of 1 are racemic mixtures based on the CD measurement. 2 and 3 are isostructural, in the structure, there are two kinds of 2D chiral helical-layers which stack in an -ABAB- sequence leading to the overall structure are mesomer and achiral. All compounds display intense luminescence in solid state at room temperature with high chemical and thermal stability. More importantly, 1 has been successfully applied in the detection of Cu 2+ ions in aqueous media and nitrobenzene and the probable detecting mechanism was also discussed. [ABSTRACT FROM AUTHOR]

Exploration of a highly effective, durable non-precious metal-based catalyst in oxygen evolution reaction remains a major challenge in the process of developing and utilizing hydrogen energy by electrocatalytic splitting water (OER). This study developed a simple and efficient method to synthesize CoFe-PBA by directly growing the Prussian blue analogues (PBAs) precursor on a self-supporting electrode with a conductive substrate, which is further phosphorized into CoFe–P/NF electrocatalyst. The high conductivity and large surface area of NF could accelerate electron transmission and increase the number of active sites. Fe incorporation could also enhance electronic structure and optimize adsorbate energy. The obtained CoFe–P/NF exhibits excellent electrocatalytic performance for the OER in 1 ​M KOH, which only provides overpotentials of 264 and 278 ​mV at current densities of 100 and 200 ​mA ​cm−2, respectively, and exhibits excellent durability over 120 ​h. This method provides a feasible strategy for exploring high-efficiency oxygen evolution reaction catalysts. The PBA precursor nanocubes of the CoFe-PBA/NF were subjected to low-temperature phosphating treatment to convert them into layered stacked nanosheets of the CoFe–P/NF, which have excellent activity and long-lasting stability for oxygen evolution reactions. [Display omitted] • PBA including multiple metals are a research hotspot for oxygen evolution catalysts. • Iron incorporation can optimize the electronic structure and reduce the adsorption energy for chemical reactions. • NF with 3D frameworks can enhance electron transport and prevent atomic agglomeration. • Cubic precursors are transformed into nanosheets scattered on NF after phosphating. • The catalyst provides overpotentials of 264 mV ​and exhibits excellent durability over 120 ​h. [ABSTRACT FROM AUTHOR]

A series of new 1D isomorphic lanthanide metal-organic frameworks (Ln-MOFs), {[Ln(L)(H 2 O) 5 ]·2H 2 O} n (1-Ln , Ln ​= ​Eu, Tb, Dy and Eu x Tb 1-x), were synthesized via a rigid bifunctional N,O-containing 2-(1 H -tetrazol-5-yl)terephthalic acid (H 2 L) and Ln(III) ions as raw materials. It is worth noting that different ratios of Eu(III) and Tb(III) can be combined into the same Ln-MOFs to generate a series of new differently doped 1-Eu x Tb 1-x MOFs. Under the same excitation wavelength, the double emission peaks of Eu(III) and Tb(III) are produced, and the emission color gradually changes between yellow-green, yellow, orange, and red. The sensing studies have shown that 1-Tb is an excellent reusable luminescence probe, suitable for simultaneous detection of dimetridazole (DMZ), metronidazole (MDZ) and tetracyclinehydrate (TET) in the aqueous solutions. Furthermore, magnetic measurements show that 1-Dy has slow magnetic relaxation properties. A series of new 1D isomorphic lanthanide metal-organic frameworks (Ln-MOFs), {[Ln(L)(H 2 O) 5 ]·2H 2 O} n (1-Ln , Ln ​= ​Eu, Tb, Dy and Eu x Tb 1-x), had been synthesized, and the 1-Eu x Tb 1−x doped MOFs achieve tunable emission from yellow-green to yellow to red. Besides, 1-Tb can be used to detect dimetridazole (DMZ), metronidazole (MDZ), and tetracycline (TET) in water and serum sensitively and selectively through fluorescence quenching, and 1-Dy has a slow magnetic relaxation performance. [Display omitted] • Series of isostructural Ln-MOFs had been synthesized by a rigid ligand. • A series of doped 1-Eu x Tb 1−x MOFs were obtained to achieve tunable emission. • 1-Tb has the high selectivity and sensitivity to detect DMZ, MDZ and TET. • 1-Dy has the slow magnetic relaxation properties. [ABSTRACT FROM AUTHOR]

In this paper, two unique 3D MOFs, namely, {[Cd 5 (L) 2 (H 2 O) 16 ]·4H 2 O} n (1), {[Pb 5 (L) 2 (H 2 O) 2 ]·6H 2 O} n (2) were obtained by taking advantage of 2,4-di(3′,5′-dicarboxylphenyl)benzoic acid (H 5 L) and Cd(Ⅱ), Pb(Ⅱ) metal ions under solvothermal conditions. The coordination diversity of the H 5 L ligand gives rise to two distinct coordination modes in 1 – 2 , which contributes to the MOFs with multifarious structures. Complex 1 exhibits a 3D 5-connected topology, and Cd(Ⅱ) metal ions of 1 show three different coordination geometries. 2 displays a 3D (2,3,4,7)-connected net on the basis of penta-nuclear [Pb 5 (μ 1 -COO) 5 (μ 2 -COO) 5 ] clusters, as well the structure of complex 2 contains specific 1D Pb– O –Pb chains. A room temperature, 1 – 2 shows eminent solid-state luminescence properties and the maximum emission peaks are ∼416 ​nm & ∼429 ​nm respectively. At the same time, due to the luminescence quenching effect of complex 1 , it reveals excellent selectivity and sensitivity for Fe3+ cations and Cr 2 O 7 2− anions with low detection limit. The fluorescence quenching mechanisms of complex 1 were also lucubrated. In this paper, two unique 3D MOFs, namely, {[Cd 5 (L) 2 (H 2 O) 16 ]·4H 2 O} n (1), {[Pb 5 (L) 2 (H 2 O) 2 ]·6H 2 O} n (2) were obtained by taking advantage of 2,4-di(3′,5′-dicarboxylphenyl)benzoic acid (H 5 L) and Cd(Ⅱ), Pb(Ⅱ) metal ions under solvothermal conditions. The coordination diversity of the H 5 L ligand gives rise to two distinct coordination modes in 1 – 2 , which contributes to the MOFs with multifarious structures. Complex 1 exhibits a 3D 5-connected topology, and Cd(Ⅱ) metal ions of 1 show three different coordination geometries. 2 displays a 3D (2,3,4,7)-connected net on the basis of penta-nuclear [Pb 5 (μ 1 -COO) 5 (μ 2 -COO) 5 ] clusters, as well the structure of complex 2 contains specific 1D Pb– O –Pb chains. A room temperature, 1 – 2 shows eminent solid-state luminescence properties and the maximum emission peaks are ∼416 ​nm & ∼429 ​nm respectively. At the same time, due to the luminescence quenching effect of complex 1 , it reveals excellent selectivity and sensitivity for Fe3+ cations and Cr 2 O 7 2− anions with low detection limit. The fluorescence quenching mechanisms of complex 1 were also lucubrated. [Display omitted] • Two novel 3D LMOFs were constructed based on a symmetrical V-shaped rigid pentacarboxylic acid ligand. • Complexes 1 and 2 feature 3D frameworks based on diverse metal chains and clusters with high open metal sites. • 1 – 2 shows eminent solid-state luminescence properties at room temperature. • Complex 1 has high selectivity and sensitivity to detect Fe3+ and Cr 2 O 7 2− ions with low detection limit. [ABSTRACT FROM AUTHOR]

To study the steric effect of the flexible dicarboxylate ligands on the resultant formations of coordination polymers (CPs), four new Pb II CPs [Pb(1,2-pda)(H 2 O)] n ( 1 ), [Pb(1,3-pda)] n · n H 2 O ( 2 ), [Pb 2 (1,4-pda) 2 (H 2 O)] n ·2 n H 2 O ( 3a and 3b ) have been produced by the isomeric phenylenediacetic acids (H 2 pda). The X-ray crystallography study reveals that CP 1 is a two-dimensional (2D) 4-connected sql (4 4 .6 2 ) network via the weak Pb···O interactions built on 1D chain-like structure. CP 2 crystallizes in orthorhombic system with chiral space group P 2 1 2 1 2 1 , showing a 4-connected sra (4 2 .6 3 .8) framework where a left-handed helical motif is formed by Pb II ions and trans -1,3-pda ligands. More interestingly, CPs 3a and 3b are two true 3D polymorphs and have the different morphology. Topologically, the framework of 3a exhibits a 4-connected lon 6 6 motif, while that of 3b is a (4,6)-connected fsh (4 3 .6 3 ) 2 (4 6 .6 6 .8 3 ) net. It is found that the three isomeric pda anions display the various coordination fashions in four CPs. The different structural arrangements show that the steric effect of the isomeric H 2 pda tectons has a positive role in directing the final products of Pb II CPs. Also, the fluorescent properties of the CPs were studied in the solid state at room temperature. [ABSTRACT FROM AUTHOR]

Two new complexes {[Cd 3 L 2 (4,4'-bipy)(H 2 O) 2 ]·2H 2 O} n (1) and {[Zn 3 L 2 (4,4'-bipy)(H 2 O)]·H 2 O} n (2), were synthesized successfully based on 5-((carboxy-3-thio) methyl)isophthalic acid (H 3 L) and 4,4'-bipyridine (4,4'-bipy) auxiliary ligands under solvothermal conditions. Complexes 1 and 2 have the three-dimensional (3D) crystal structures, which contain infinitely extended one-dimensional (1D) metal chains decorated by open metal sites (OMSs). 1 and 2 both show good thermal stability and excellent water resistance. Fluorescence tests showed that complex 1 has high selectivity and sensitivity to detect Fe3+, Cr 2 O 7 2− and CrO 4 2− ions in aqueous solution. In addition, complex 1 is an excellent heterogeneous catalyst for the cycloaddition of CO 2 and epoxides that catalytic efficiency of epichlorohydrin is higher than 99% under mild conditions. Two new complexes {[Cd 3 L 2 (4,4'-bipy)(H 2 O) 2 ]·2H 2 O} n (1) and {[Zn 3 L 2 (4,4'-bipy) (H 2 O)]·H 2 O} n (2) were synthesized. 1 as a fluorescent probe can detect Fe3+, Cr 2 O 7 2− and CrO 4 2− ions in aqueous solution quickly and accurately with low detection limit especially. Meanwhile, complex 1 exhibits great catalytic performance for CO 2 and epoxides due to the abundant open metal sites (OMSs) embellished the 1D channel. [Display omitted] • Two new complexes were constructed based on 5-((carboxy-3-thio) methyl)isophthalic acid. • Complexes 1 and 2 feature 3D porous frameworks with high open metal sites. • Complex 1 has high selectivity and sensitivity to detect Fe3+, Cr 2 O 7 2− and CrO 4 2− ions. • The desolvated 1 exhibits great catalytic performance for CO 2 and epoxides under mild conditions. [ABSTRACT FROM AUTHOR]

Abstract: A new three-dimensional porous framework [Co2(bpdc)2(H2bpz)]∙2(DMF)·5(H2O) (1) (H2bpdc=4,4′-biphenyldicarboxylic acid, H2bpz=3,3′,5,5′-tetramethyl-4,4′-bipyrazole) has been solvothermally synthesized by employing mixed H2bpdc and H2bpz ligands. 1 is a pillared-layer framework based on a binuclear paddle-wheel Co2(O2C-R)4 cluster, and exhibits a 2-fold interpenetrated 6-connected pcu topology. H2bpz bridges Co2(O2C-R)4 clusters with an angular coordination configuration to form interesting left- and right-handed helical chains. 1 possesses a two-dimensional porous system decorated by uncoordinated pyrazole –NH groups of H2bpz, leading to high adsorption selectivities for CO2 over N2 and H2. In addition, the strong antiferromagnetic interactions between the Co2+ ions in cluster were observed. [Copyright &y& Elsevier]

Herein, three new solvents induced metal-organic frameworks (MOFs), [Zn(H 2 L)H 2 O] (1), [Zn 2 (L)H 2 O] (2) and [Zn 3 (HL) 2 ]·(CH 3 CN) 2 (3) were synthesized via the solvothermal reaction procedure by using a rigid v-shaped 3,5-di (2,4-dicarboxylphenyl)pyridine (H 4 L) and Zn(II) ions. Structural analyses show that the organic ligand H 4 L adopt various degrees deprotonation (H 2 L2− for 1 ; L4− for 2 and HL3− for 3), which obtain different structures for three new MOFs: 2D layer network for 1 ; 3D dense packing structure for 2 and 3D porous structure with the pore size of 10.3 ​× ​10.6 ​Å2 for 3. The gas sorption behavior of the guest-free phase 3' shows an ultra-high adsorption selectivity and affinity for CO 2 over CH 4. The experiment results provide us with a reasonable facile route for designing and synthesizing new potential gas sorption and separate materials in CO 2 purification. And the solid-state luminescence properties of 1 – 3 were measured and studied intensively at room temperature. Three new solvents induced metal-organic frameworks (MOFs), [Zn(H 2 L)H 2 O] (1), [Zn 2 (L)H 2 O] (2) and [Zn 3 (HL) 2 ]·(solvent) (3) were synthesized via the solvothermal reaction procedure by using a rigid V-shaped 3,5-di (2,4-dicarboxylphenyl)pyridine (H 4 L) and Zn(II) ions. Gas sorption of 3' displays an ultra-high adsorption selectivity and affinity for CO 2 over CH 4. And the solid-state luminescence properties of 1 – 3 were measured and studied systematically at room temperature. [Display omitted] • Solvents induced three new metal-organic frameworks (MOFs), [Zn(H 2)LH 2 O] (1), [Zn 2 (L)H 2 O] (2) and [Zn 3 (HL) 2 ]·[solvent] (3) were synthesized via the solvothermal reaction procedure by using a rigid V-shaped 3,5-di (2,4-dicarboxylphenyl)pyridine (H 4 L) and Zn(II) ions. • Structural analyses show that the organic ligand H4L adopt various degrees deprotonation (H 2 L2− for 1 ; L4− for 2 and HL3− for 3), which obtain different structures for three new MOFs: 2D layer network for 1; 3D dense packing structure for 2 and 3D porous structure with the pore 10.3 ​× ​10.6 ​Å2 for 3. • Gas sorption behavior of 3′ shows an ultra-high adsorption selectivity and affinity for CO 2 over CH 4. • The solid state luminescent 1 – 3 have been explored in detail, which shows the red and blue shift in compared with H 4 L. [ABSTRACT FROM AUTHOR]

Four new complexes, namely {[Cd(L1) 2 ·(H 2 O)·(DMA)} n (1), {[Zn(L1) 2 (HL1)]·3.5H 2 O} n (2), {[Pb(L2)(HCOO)]·0.5H 2 O·0.5DMF} n (3), and {[Zn(L2)(NO 3)(H 2 O)]·0.5H 2 O·0.5CH 3 CN} n (4), were synthesized by two isomeric (2-(pyridin-4-yl)-benzimidazole-5-carboxylic acid) (HL1) and (2-(pyridin-2-yl)-benzimidazole-5-carboxylic acid) (HL2) under hydro(solvo) thermal conditions. The ligands in the complexes adopt different coordination modes to connect the metal centers and finally form three-dimensional structures with different pore size. The results of fluorescence tests show that complex 3 has high sensitivity and selectivity to both Fe3+and MnO 4 −, the quenching constants are 8.74 ​× ​104 ​L ​mol−1 and 3.88 ​× ​104 ​L ​mol−1, and the minimum detection limit are 1.17 ​× ​10−5 ​mol ​L−1 and 4.48 ​× ​10−5 ​mol ​L−1, respectively. In addition, complex 1 has fast and efficient adsorption capacity for Congo red (CR) and Methyl green (MG). Four new functional MOFs were synthesized successfully based on two isomeric ligands which present multiple coordination modes in the complexes. Complex 1 shows an excellent adsorption behavior for Congo red (CR) and Methyl green (MG) especially; Complex 3 exhibits an extremely good specific selectivity and sensitivity to Fe3+ and MnO 4 − ions. Image 1 [ABSTRACT FROM AUTHOR]

Three new luminescent metal-organic frameworks (MOFs), {[Zn(L)(H 2 O)]·2H 2 O} n (1), {[Pb(L)]·0.5DMA} n (2), and {[Cd 2 (L) 2 (H 2 O) 2 ·2H 2 O} n (3) were synthesized by an asymmetric N-containing 2-pyrimidin-5-yl-terephthalic acid (H 2 L) ligand with Zn2+, Pb2+, and Cd2+ ions, respectively. In these complexes, L2− ligand exhibits the multiple coordination modes with metal ions to form different new structures; especially there exist the different secondary building units (SBUs) in 2 and 3. The solid-state luminescent properties of complexes 1-3 were studied at room temperature and the mechanism was analyzed carefully. In particular, complex 2 has good stability in aqueous solution and exhibits the specific selectivity and sensitivity to probe Fe3+, MnO 4 −, CrO 4 2− and Cr 2 O 7 2− simultaneously, and the detection limits of Fe3+ and Cr 2 O 7 2− ions are 5.6 ​× ​10−5 and 10−6, respectively. These are lower than those of other reported sensors. Finally, its quenching mechanism has also been studied in detail. Three new luminescent MOFs were synthesized successfully, where the L2− ligand exhibits the multiple coordination modes with metal ions to form new different structures; especially there exist the different secondary building units (SBUs) in 2 and 3. Complex 2 has good stability in aqueous solution and exhibits the specific selectivity and sensitivity to Fe3+, MnO 4 −, CrO 4 2− and Cr 2 O 7 2− ions. Image 1 • Three new luminescent MOFs with Zn2+, Pb2+, and Cd2+ ​ions were prepared successfully by a new N-containing ligand. • The L2- ligand may exhibit the multiple coordination modes with various metal ions to form different new structures. • The solid-state luminescent properties of ​ 1-3 ​were studied at room temperature and the mechanism was analyzed. • Complex ​ 2 ​can selectively probe Fe3+, MnO 4 −, CrO 4 2− ​and Cr 2 O 7 2− ​simultaneously in the aqueous solution.The detection limit can reach 10-4 ​to 10-6, which is lower for detection with those of the reported sensors. [ABSTRACT FROM AUTHOR]

Two new metal-organic frameworks (MOFs), [Cd 4 (L1) 2 (H 2 O) 4 ·3(H 2 O)·DMA (1) and (Me 2 NH 2) 2 [Cd 2 (L1)(L2)]·[solvent] (2) (DMA ​= ​N,N-Dimethylacetamide) were successfully synthesized via the solvothermal reaction procedure by a rigid V-shaped N-heterocyclic 2,6-di(2′,5′-dicarboxylatephenyl)pyridine (H 4 L1) ligand, terephthalic acid (H 2 L2) and Cd(II) ions in this work. Structural analyses show that the carboxylate groups of L14− adopt different coordination modes with Cd(II) ions in 1 and 2 , which form the different secondary building units (SBUs) to yield two new different 3D MOFs. Compared with 1 , the introduction of the terephthalic acid (H 2 L2) produces 2 with potential solvent area volume 51.9% (2608.5 ​Å3, per unit cell volume 5029.2 ​Å3). The gas sorption and luminescent experiments of 2 show the high selectivity of CO 2 over CH 4 and selective sensitivity for Fe3+ and Cr 2 O 7 2− ions in aqueous solution. The experiment results offer a facile route for designing and yielding new potential multi-functional MOF materials in gas sorption and detecting Fe3+ and Cr 2 O 7 2− ions. Two new metal-organic frameworks (MOFs) were successfully synthesized via the solvothermal reaction by using Cd(II) ions with a rigid V-shaped nitrogen heterocyclic carboxylic acid ligand (H 4 L1) and terephthalic acid (H 2 L2). Gas sorption and luminescent properties of 2 were systemically explored. The results show 2 had high selectivity for CO 2 over CH 4 and sensitivity for Fe3+ and Cr 2 O 7 2− ions in aqueous solution. Image 1 • Two new metal-organic frameworks (MOFs) were successfully synthesized by using a rigid V-shaped N-heterocyclic 2,6-di(2',5'-dicarboxylatephenyl)pyridine (H 4 L1) ligand, terephthalic acid (H 2 L2) and Cd(II) ions. • Structure analysis revealed that 1 is a 3D dense packing structure, 2 is porous structure with potential solvent area volume 51.9% (2608.5 Å3, per unit cell volume 5029.2 Å3). • Gas sorption measurements reveled that 2 showed the higher adsorption selectivity for CO 2 over CH 4. • The luminescent experiments of 2 show the high selective sensitivity for Fe3+ and Cr 2 O 7 2- ions in aqueous solution. [ABSTRACT FROM AUTHOR]

The self-assembly of Zn2+ ion and an azolyl-carboxyl bifunctional ligand, 4,6-bis(triazol-1-yl)isophthalic acid (H 2 btzip), give rise to one three-dimensional (3D) porous metal-organic framework (MOF), [Zn(btzip)(H 2 O) 0.5 ]·H 2 O (1). The MOF shows a rare (4,8)-connected scu net containing 1D channels, based on 4-connecetd ligands and 8-connected [Zn(COO) 2 (H 2 O)] dimers. Owing to the decoration of uncoordinated N atoms in porous walls, 1 can selectively capture CO 2 molecules over CH 4 with high adsorption heat and considerable selectivity. The different adsorption sites for CO 2 in 1 were deeply explored by simulations. In addition, 1 also displays strong solid-state luminescence that is from the intraligand charge transfer. One new Zn-MOF with a rare (4,8)-connected scu topology was constructed by a azolyl-carboxyl bifunctional ligand, which contains polar channels decorated by uncoordinated N atoms and displays adsorption selectivity for CO 2 over CH 4 and luminescent properties as well. Image 1 • One Zn-MOF with a scu topology was constructed by an azolyl-carboxyl ligand. • The MOF with polar channels shows selectively capture for CO 2 over CH 4. • Theoretical simulations reveal accessible N adsorption site for CO 2 molecules. • The MOF displays strong solid-state luminescence. [ABSTRACT FROM AUTHOR]