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Four new coordination polymers, including 1D, 2D and 3D structures, were synthesized via a hydrothermal method using Cd2+/Zn2+/Cu2+ metal salts as nodes. These polymers were formed through self‐assembly of four different dicarboxylic acid ligands, namely adamantane‐1,3‐dicarboxylic acid (H2adc), glutaric acid (H2glu), 5‐hydroxyisophthalic acid (H2hip) and fumaric acid (H2fum), in conjunction with the auxiliary ligand [1,4‐bis(pyridin‐4‐ylmethyl)piperazine (bpmp). The corresponding formulae are [Cd3(adc)2(bpmp)Cl2(H2O)2]n (1), {[Cd2(glu)2(bpmp)2(H2O)2]·8H2O·2CH3OH}n (2), [Zn(hip)(bpmp)(H2O)]n (3) and [Cu(fum)(bpmp)(H2O)2]n (4). Single‐crystal X‐ray diffraction studies revealed that the Cd2+ centers in complex 1 all adopt a six‐coordinate mode but two distinct {CdO2N2Cl2} and {CuO5Cl} units. The 3D network of complex 1 can be simplified to a binodal (4.6)‐connected underlying net with the point symbol (3·42·5·62)4(32·62·72·88·10). Each Cd2+ cation in complex 2 adopts a seven‐coordinate {CdO5N2} center, forming an asymmetric pentagonal bipyramidal coordination. Its stacking structure is formed by the interaction of hydrogen bonds between 2D supramolecular layers, with the adjacent layers exhibiting mirror symmetry. Each Zn2+ ion in complex 3 displays a {ZnO3N} four‐coordinate unit. Its stacking structure is formed by one‐dimensional [Zn(hip)(bpmp)(H2O)]n chains connected through hydrogen bonds. On the other hand, complex 4 features a Jahn–Teller distorted {CuO4N2} octahedral coordination. Subsequently, the thermal stability of these complexes was investigated. The solid‐state fluorescence spectroscopy was employed to analyze complexes 1, 2 and 3. Additionally, a Hirshfeld surface analysis was performed on complex 3. [ABSTRACT FROM AUTHOR]

Four new coordination frameworks with formulas of {[Co(fdca)(4-bpmp)(H2O)2]·2H2O}n (1), {[Ni(fdca)(4-bpmp)(H2O)2]·2H2O}n (2), [Co(tdca)(4-bpmp)(H2O)]n (3) and [Co(fuma)(4-bpmp)(H2O)2]n (4) [4-bpmp = bis (4-pyridylmethyl)piperazine, fdca = 2,5-furandicarboxylic acid, tdca = 2,5-thiophenedicarboxylic acid, fuma = fumaric acid] have been synthesized and structurally characterized by elemental analysis, single-crystal X-ray diffraction analysis and thermogravimetric analysis. Complex 3 exhibits a 4-connected sqc6 uninodal 3D structure with point symbol of {66}, while the other three complexes all exhibit mutually inclined 2D + 2D → 3D interpenetration structures. The magnetic properties reveal that complex 1, 2, and 4 show the antiferromagnetic exchange interaction behavior. An observed difference in structure and magnetic behavior in complex 3 is driven by coordination types of carboxylate building blocks and the final structure. Magnetic study indicates the magnetic-exchange coupling not only depends on the nature of the metal centers but the structure of the metal–organic framework can affect the magnetic. And then, the UV–Vis DRS properties of four complexes were also investigated. [ABSTRACT FROM AUTHOR]

Herein, three new coordination polymers (CPs), namely {Ni (4,4′-abpt)(2,5-fdca)H2O]n (1), [Co(4,4′-abpt)(2,5-fdca)H2O]n (2) and [Co(4,4′-abpt)(1,3-abc)]n (3) {4,4′-abpt = 3,5-di-4-pyridinyl-4H-1,2,4-triazol-4-amine, 2,5-fdca2− (the fully deprotonated forms of 2,5-furandicarboxylic acid), 1,3-abc2− (the fully deprotonated forms of 1,3-adamantanedicarboxylic acid)} were synthesized under solvothermal conditions and were characterized by elemental analysis, thermogravimetric analysis, powder X-ray diffraction, and single crystal X-ray diffraction (1 and 3) techniques. Structural analyses revealed that 1 is a two-dimensional structure with quadrilateral holes, while 3 is a two-dimensional rhombus network configuration with a binuclear metal center. Three as-prepared compounds exhibited efficient photocatalytic performance for the degradation of organic dyes of crystal violet (CV), methylene blue (MB), and rhodamine B (Rh-B) under UV irradiation, among which, 1 exhibited the best photocatalytic activity with a percentage degradation of more than 96% for the three dyes in 30 min. In addition, in the free radical capture experiment involving 3, it was found that both, the hydroxyl radical OH˙ and superoxide radical (˙O2−) were involved in the degradation process of dyes, among which, the OH˙ radical is the main species to trigger the photocatalytic degradation experiment. Finally, the electrocatalytic performance of the catalysts was investigated in 1 M alkaline KOH solution, and the results showed that all three catalysts had certain electrocatalytic performance, and the catalytic performance of 1 was slightly better than that of 2 and 3. It exhibited a low overpotential of 367 mV at a current density of mA cm−2. [ABSTRACT FROM AUTHOR]

Three new metal–organic coordination polymers, {[Co2(TDC)2(H-3,3′-pytz)2(μ2-OH)]·4DMF}n (1), [Mn5(NDC)4(3,3′-pytz)(DMF)4(μ3-OH)2]n (2), [Co5(NDC)4(3,3′-pytz)(DMF)4(μ3-OH)2]n (3). (3,3′-pytz = 3,6-bis(3-pyridyl)-1,2,4,5-tetrazine; H-3,3′-pytz = protonated 3,6-bis(3-pyridyl)-1,2,4,5-tetrazine; H2TDC = 2,5-Thiophenedicarboxylic acid; H2NDC = 1,4-naphthalenedicarboxylic acid) were synthesized under hydro-/solvothermal conditions and characterized by techniques of single-crystal X-ray diffraction analysis, elemental analysis, infrared spectra (IR) and thermogravimetric analysis (TGA). The resulting analyses demonstrate that complex 1 displays a rare 3D 8-connected bcu framework with the point symbol of {424·64} based on dinuclear [Co2(μ2-OH)(COO)4] cluster, while complex 2 and 3 possessed a rare 3D 10-connected pentanuclear-cluster-based ile{36·434·53·62}framework. The variable-temperature magnetic susceptibility data show that the complex 1, 2 and 3 exhibit antiferromagnetic interaction. [ABSTRACT FROM AUTHOR]