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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]

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]

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 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]

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]

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]