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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]

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]

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]

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]

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]