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Two new isomorphic metal complexes, [M(phon)(H2O)4]·SO4·2H2O (M = Ni and Zn, 1-Ni and 1-Zn, respectively, phon = 1,10-phenanthroline-5,6-dione), were crystallized at room temperature. Single-crystal X-ray analyses reveal that a metal ion is coordinated with one phon ligand and four coordinated water molecules into a discrete coordination structure which expands into a 3D supramolecular structure via hydrogen bonding interactions. The thermal and electrochemical properties of the complexes are investigated. The results show that 1-Ni exhibits redox activity under alkaline conditions and has potential to act as a redox reaction mediator, while 1-Zn does not. The specific capacitance of 1-Ni0.5Zn0.5, obtained by mixing the two complexes under hydrothermal condition, is four times higher than that of 1-Ni. [ABSTRACT FROM AUTHOR]

Five new zinc coordination polymers based on flexible carboxylate ligands, namely, [Zn2(chtc)(H2O)]·3H2O (1), [Zn2(chtc)(4,4′-bpy)0.5] (2), [Zn(H2chtc)(bpe)] (3), [Zn(cis-chdc)(bpe)]·3H2O (4), and [Zn(trans-chdc)(bpe)(NO3)(H2O)]·H2O (5) (chtc/H2chtc = deprotonated/half-protonated cyclohexane-1e,2a,4a,5e-tetracarboxylic acid, cis/trans-chdc = cyclohexane-1e,2a/1e,2e-dicarboxylic acid, 4,4′-bpy = 4,4′-bipyridine, bpe = trans-1,2-(bis(4-pyridyl)ethene)) have been constructed and characterized. Owing to the tunability of linking ligands, these complexes show different interesting topological networks, namely uninodal umc three-dimensional network for 1, mtc three-dimensional non-manifold topology for 2, (4,4) net for the two-dimensional structure of 3, dmp-c interpenetrated network for 4, and one-dimensional ladder chain for 5. Notably, all complexes exhibit selectivity and sensitivity for Fe3+ ions with detection limit of less than 3.5 μM, which was correlated to the dimensionalities of the structures, implying their potential application in sewage detection. [ABSTRACT FROM AUTHOR]

Two alkaline-earth metal coordination polymers, [Ca(TAPIP)2(H2O)3]·2H2O (1) and [Ca(TAPIP)2(H2O)3]·5H2O (2), have been synthesized under hydrothermal reactions with the imidazo[4,5-f][1, 10]phenanthroline derivate D-π-A type ligand, 2-(4-(1H-1,2,4-triazol-1-yl)phenyl)-1H-imidazo[4,5-f][1, 10]phenanthroline (TAPIP). Complexes 1 and 2 crystallize in different lattice groups and are discrete coordinate structures in which the two planes of TAPIP ligands are nearly coplanar and perpendicular, respectively. Moreover, in 2 an interesting infinite water chain is captured. In exploring their one/two-photon excited fluorescence, the results show that the original ligand and 1 exhibit similar fluorescent properties while 2 gives off orange light and shows much stronger two-photon excited fluorescent properties which might result from the different torsion angles and/or stacking modes of the organic ligands. [ABSTRACT FROM AUTHOR]

Abstract: Five lanthanide coordination polymers with composition {[Ln(pzdc)1.5(H2O)3]·0.5H2O} ∞ , (Ln=Pr, 1; Nd, 2; Sm, 3; Eu, 4; Gd, 5; pzdc=2,5-pyrazinedicarboxylate), have been synthesized by reacting Ln(NO3)3 ·6H2O with 2,5-pyrazinedicarboxylic acid under hydrothermal condition in the absence of additional base and characterized by elemental analysis, IR spectra and TG analysis, as well as single-crystal X-ray diffraction. They crystallize isostructurally in the triclinic space group P-1 and the cell parameters agree with the ionic radii of the Ln(III) ions. Each trivalent rare earth ion is nine coordinate in an N2O7 environment. The ligand 2,5-pyrazinedicarboxylate adopts three coordination modes, through which the lanthanide ions are linked together to form an infinite three dimensional structure. A 1D channel exists along the (100) direction which accommodates uncoordinated water by hydrogen bonds. Heating of 4 at 120°C evacuated the uncoordinated water while retaining its single crystallinity with only minor change in cell parameters (crystal 6, [Eu(pzdc)1.5(H2O)3] ∞ ). This hydrophilic ultramicroporous channel is selective to accommodate water only among common solvents, which has some potential interest for solvent separation. [Copyright &y& Elsevier]

A new Zn-based complex with 2D network was synthesized and fully showed selective luminescence quenching for benzaldehyde vapor with LOD of 19.6 mg·L-1 through photoinduced electron transfer mechanism. [Display omitted] • Synthesis of a new 2D coordination structure with sulfate bridging moieties. • Selective luminescence detection of benzaldehyde vapor or ethanol solution. • The limit of detection for volatile benzaldehyde is firstly calculated. • Detail study of the luminescence quenching mechanism. Benzaldehyde (BZH) is a hazardous substance that can cause respiratory irritation and acute poisoning if it leaks excessively into the environment. Fluorescence detection of BZH is common in liquid phase, but still rare in gas phase. In this study, we synthesized a new complex, [Zn(bpe)(SO 4)(H 2 O)]·2H 2 O (Zn-bpe), with two-dimensional layered structure. Interestingly, it exhibited good fluorescence quenching behavior not only for BZH dissolved in ethanol, but also for volatile BZH which is detected on thin films prepared by combining complexes with polyvinyl alcohol (Zn-bpe@PVA). Moreover, the limit of detection (LOD = 19.6 mg·L-1) of the latter is firstly calculated through the linear fitting of emission intensities. The quenching mechanism was attributed to the energy transfer from the complex to BZH molecules, which was confirmed by in situ IR spectra and DFT calculations. [ABSTRACT FROM AUTHOR]

A novel 2D manganese MOFs exhibits selective photodegradation of bromocresol green which can be promoted by moisture owing to the sensitivity for the Mn-O bonds. [Display omitted] • Synthesis and characterization of 2D corrugated structure. • Selective photodegradation of BCG. • Promotion of degradation of BCG by Moisture owing to the sensitive of coordination bonds. Three new isostructural metal-organic frameworks, [M 2 (D-cam) 2 (4,4′-bpy)(H 2 O) 4 ] (D-cam2- = D-camphorate, 4,4′-bpy = 4,4′-bipyridine, M = Mn (1-Mn), Co (1-Co), and Ni (1-Ni)), have been synthesized and fully characterized. The complexes, crystallizing in chiral space group, P2 1 , are AA-stacking corrugated layers with hcb topological networks composed of homochiral coordination chains, M(D-cam), and auxiliary ligands. Notably, the solubility in water for three MOFs decrease in accordance with Irving-Williams series, indicating the good moisture-sensitivity for 1-Mn. Furthermore, the photolysis experiments of dyes reveal that only 1-Mn can catalyze the degradation of bromocresol green (BCG) rapidly and selectively, which can pave a way to explore more prolific functional MOFs in catalysis. CCDC: 2158741. [ABSTRACT FROM AUTHOR]

Two series of lanthanide coordination polymers, {[Ln 2 (tabc) 4 (C 2 O 4 )(H 2 O) 5 ]·H 2 O} n (Ln = Nd ( 1 ), Sm ( 2 ), Eu ( 3 ), Htabc = 4-(1–1,2,4-triazolyl)benzoic acid) and {[Sm(tabc)(1,2-pdc)(H 2 O) 2 ]·2H 2 O} n ( 4 ), have been constructed via hydrothermal conditions through adding different auxiliary ligands. Compounds 1 – 3 are two dimensional coordination layer comprised of {Ln1(COO) 2 } chains and {Ln2(COO) 2 } dinuclear units which are connected by oxalate groups, whereas compound 4 is one dimensional chain containing {Sm 2 (COO) 2 } dinuclear units. The IR spectra and thermal stabilities of all compounds have been studied in detail. Compound 3 shows characteristic emission of Eu3 + ions, and it is noteworthy that the luminescent properties for 2 shows no emission peaks whereas that for 4 exhibits characteristic absorption bands of Sm 3 + ions. CCDC: 1478487, 1478488, and 1478495 [ABSTRACT FROM AUTHOR]

Abstract: Two mixed-valence CuICuII coordination polymers [CuICuII(qdiol)ClL] n (qdiol2−=2,3-dioxyquinoxalinate, L=2,2′-bipyridine, 1; L=1,10-phenanthroline, 2) were obtained in basic ethanolic solution of CuCl2, 1,4-dihydro-2,3-quinoxalinedione and L under the solvothermal condition. 1 and 2 are similar in composition, but differ remarkably in structure. The coordination modes of CuII, qdiol2− and L are identical in both complexes. But the CuI ions are two- and three-coordinated, and the Cl− ions are terminal and bridging, in 1 and 2, respectively, which are relevant to the significantly different C–H⋯Cl hydrogen bonding pattern of bpy and phen. The temperature variable magnetic susceptibilities show that 1 is paramagnetic and 2 is weakly antiferromagnetic. The complex impedance spectroscopic studies indicate that both 1 and 2 are semiconductors and 2 is more conducting. [Copyright &y& Elsevier]