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Through a mixed-ligand strategy, the structural change from a discrete dinuclear DyIII cluster to a one-dimensional polymeric chain was achieved, maintaining the two magnetic entities with the same {Dy(dppbO2)2(H2O)5} (dppbO2 = 1,4-butylenebis(diphenylphosphine oxide)) core structure. Since the hydrogen bonding between the equatorial coordinated water molecules and the guests/solvents/anions is distinct, the local geometry and the equatorial planarity of the first coordination sphere of the central DyIII ion become slightly different caused by the second coordination sphere. As a result, the dinuclear compound shows typical butterfly-shaped hysteresis loops, while it significantly opens at zero magnetic field up to 11 K for the 1D polymer, which is unprecedented in coordination polymers. Our experimental observations and theoretical analysis indicate that the hydrogen bonding leads to the fine-tuning of certain bond lengths and angles of the coordination environment, as well as the crystal field to a certain extent, revealing that the second coordination sphere affects the first coordination sphere by hydrogen bonding. [ABSTRACT FROM AUTHOR]

Three new compounds, namely, [Mn(hpcH)(H2O)2]·H2O (1), [Cd(hpcH)(DMF)(H2O)] (2), [Cu(hpcH2)2(H2O)2] (3), (hpcH3 = 5-hydroxy-1H-pyrazole-3-carboxylic acid) were solvothermally synthesized and characterized in detail. Compounds 1 and 2 are coordination polymers (CPs), exhibit two-dimensional (2D) layered structures and crystallize in monoclinic lattices with the C2/c and P21/c space groups, respectively. Compound 3 shows a 3D supramolecular structure constructed from six-coordinated mononuclear Cu2+ through hydrogen bonds and π–π stacking interactions. The hpcH3 ligand behaved in different coordinated modes in the three compounds. It lost two protons in compounds 1 and 2 and one proton in compounds 3. Furthermore, the photocatalytic degradation properties of compounds 1 and 2 were investigated. The results indicate that 1 and 2 show excellent photocatalytic activities for methylene blue (MB) under visible light. The photocatalytic degradation efficiency of 2 reached 96.7% in 90 minutes. The possible photocatalytic mechanisms displayed by CPs 1–2 for the photodegradation of MB have been addressed through the trapping experiment and theoretical calculations. [ABSTRACT FROM AUTHOR]

Solvothermal reactions of AgNO3 with 9,10-anthraquinone-1,5-dicarboxylic acid (H2L) and 4,4'-bipyridine (bipy) gave rise to a metal-organic framework, namely [Ag(L)(bipy)]n (1), which was structurally characterized by elemental analyses, IR spectra, and X-ray diffraction analysis. Single-crystal X-ray diffraction analyses indicate that 1 exhibits a 2D 44 topology framework assembled by dinuclear [Ag2(COO)2] units, L and bipy ligands. 1 displays highly sensitivity in the detection of nitrobenzene (NB) as a fluorescent sensor. Moreover, 1 exhibits a relatively good photocatalytic activity towards the degradation of rhodamine B (RhB) in aqueous solution under UV irradiation. [ABSTRACT FROM AUTHOR]

An unprecedented two-step spin-crossover behavior with the sequence of γHS=1↔ γHS=3/4↔ γHS=1/4 was observed in two-dimensional Hofmann type coordination polymer [Fe(isoq)2{Ag(CN)2}2] (isoq=isoquinoline), which resulted from three crystallographically inequivalent FeII sites with distinct transition temperatures. [ABSTRACT FROM AUTHOR]

Eight isostructural lanthanide coordination polymers [Ln(bptc)(phen)(H2O)]n (Ln = Dy for 1, Eu for 2, Tb for 3, Gd for 4, Sm for 5, Nd for 6, Yb for 7, Pr for 8) were successfully prepared based on bridging asymmetric polycarboxylate ligand biphenyl-3,2′,5′-tricarboxylic acid (H3bptc) and chelating 1,10-phenanthroline (phen) coligand. Single crystal X-ray analysis reveals that complexes 1–8 have a (3,6)-connected CdI2-type coordination network consisting of paddle-wheel dimers [Ln2(CO2)4]. The magnetic and fluorescent properties of 1–8 have been investigated. Significantly, the Dy(iii) complex 1 behaves with slow relaxation of the magnetization, where the frequency-dependent out-of-phase signals are noticed. [ABSTRACT FROM AUTHOR]

A Hoffman-like coordination polymer with appreciable porosity and uncoordinated pyridyl groups, namely, [Fe(2,5-bpp){Au(CN)2}2] ⋅ x Solv (2,5-bpp=2,5-bis(pyrid-4-yl)pyridine; Solv=solvent), was synthesised and characterised. A series of fascinating spin-crossover behaviours with abrupt, stepwise and hysteretic features were obtained by exchange with a range of protic solvents (ethanol, n-propanol, isopropyl alcohol, sec-butanol and isobutanol). Guest-host hydrogen-bonding interactions involving the H-accepting site of the framework are primarily responsible for the pronounced cooperativity of these spin-crossover behaviours. Meanwhile, the tunable critical temperatures over a range of about 130 K are presumably attributable to a certain degree of competition between internal pressure and local electronic influences of solvents. [ABSTRACT FROM AUTHOR]

The transformation of MnII glycolates (glc) between the three-dimensional coordination polymer [Mn(glc)2] n ( 1) and discrete mononuclear phase [Mn(glc)2(H2O)2] ( 2) can be reversibly switched by water molecules, which dramatically change the magnetocaloric effect (MCE) of MnII glycolates from the maximum of 6.9 J kg−1 K−1 in 1 to 60.3 J kg−1 K−1 in 2. This case example reveals that the effect of magnetic coupling on MCE plays a dominant role over that of other factors such as magnetic density for 3d-type magnetic refrigerants. [ABSTRACT FROM AUTHOR]

Two new Cd(II) coordination polymers, namely [Cd(HOA)(μ-HO)(HO)]·3 nHO (1) and [Cd(HOA)(phen)]· nHO ( 2) (HOA = 3,3′,4,4′-oxidiphthalic acid, phen = 1,10-phenanthroline) have been synthesized by combining HOA or HOA and phen with Cd(II) salts under hydrothermal conditions. Single-crystal X-ray diffraction analysis reveals that 1 features a hydrogen-bond directed two-dimensional (2D) layered structure constructed from alternating left- and right-handed double strand helical chains, 2 represents a one-dimensional (1D) chain structure with the phen molecules dangling on it, which is further extended into a three-dimensional (3D) supramolecular framework through strong face-to-face π···π interactions. In addition, luminescent properties of these two compounds were also investigated in the solid state at room temperature. [ABSTRACT FROM AUTHOR]

Two kinds of inorganic gadolinium(III)-hydroxy 'ladders', [2× n] and [3× n], were successfully trapped in succinate (suc) coordination polymers, [Gd2(OH)2(suc)2(H2O)] n ⋅ 2 n H2O ( 1) and [Gd6(OH)8(suc)5(H2O)2] n ⋅4 n H2O ( 2), respectively. Such coordination polymers could be regarded as alternating inorganic-organic hybrid materials with relatively high density. Magnetic and heat capacity studies reveal a large cryogenic magnetocaloric effect (MCE) in both compounds, namely (Δ H=70 kG) 42.8 J kg−1 K−1 for complex 1 and 48.0 J kg−1 K−1 for complex 2. The effect of the high density is evident, which gives very large volumetric MCEs up to 120 and 144 mJ cm−3 K−1 for complexes 1 and 2, respectively. [ABSTRACT FROM AUTHOR]

In this article, two different anionic ligands, 3,4-oxybis(benzoate) (bopH2) and sulfate, have been employed as co-ligands to perform a comparison on the structures of coordination polymers based on the Zn(II)–rigid 1,4-bis(imidazol-1-yl)benzene (bib) net. Two new coordination polymers, {Zn(bib)(bop)}∞ (1) and {Zn(bib)(SO4)}∞ (2), were synthesized from hydrothermal reactions and characterized by elemental analyses, IR and single-crystal X-ray diffraction. Complex 1 contains two unique 2-D layers, which are further interpenetrated to form a two-fold 2-D → 2-D framework. However, 2 consists of a 3-D structure with pcu topology constructed by sulfates as pillars. The structural difference of 1 and 2 indicates that size of the ancillary ligands play important roles in formation of such coordination architectures. Thermal and fluorescence properties of 1 and 2 are also investigated in the solid state. [ABSTRACT FROM AUTHOR]

Four novel In3+ and Cd2+ based 1D coordination compounds constructed by double betaine ligands were synthesized and characterized structurally and optically. They assemble into 3D supra‐molecular architectures via different stacking or entanglement of 1D zigzag shaped chains, in which C–H···Cl and C–H···O hydrogen bonding interactions play a dramatic impact. Compound 1 displays a 1D + 1D → 3D four‐connect lvt net with 42·84 topology. Compound 2 assembles into a 3D architecture by inclined stacking of the adjacent zigzag chains. Compound 3 displays a 2D + 2D → 3D inclined polycatenation based on the resulting 2D (6, 3) layers that constructed by 1D chains. Compound 4 displays a 3D supra‐molecular architecture based on 1D chains, which were connected via the hydrogen bonding. Meanwhile, four compounds emit in the range of visible region owing to the intra‐ligand π*→π and/or π*→n electron transition induced florescence. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis and characterization of three new Cu-based coordination polymers (CPs): [Cu(NO 3) 2 (DTP) 2 (H 2 O) 2 ] n (Cu-1), (DTP = 3,5-di(1,2,4-triazol-1-yl)pyridine), [Cu(ClO 4) 2 (DTP) 2 ] n (Cu-2), and [Cu(SO 4)(DTP)(H 2 O)] n (Cu-3). • Cu-1 , Cu-2 , and Cu-3 exhibited moderate Cu2+ release rates, indicating that the Cu-CPs could provide steady and prolonged release of Cu2+ to ensure antimicrobial performance. • The anti-bacterial and anti-fungal activities of Cu-1 , Cu-2 , Cu-3 were investigated experimentally, where the materials exhibited significant inhibition ability towards three bacteria (E. coli , X. campestris , and X. oryzae) and four fungi (P. piricola , F. oxysporum , A. alternata , and G. ciningulaia). • A preliminary investigation of the inhibition mechanism was carried out by fluorescent double staining, agarose gel electrophoresis, and SEM. The antimicrobial activities of the three Cu-CPs may be attributed to the released free Cu2+ and DTP from the CPs. • Cu-1 barely affected the growth of Bacillus subtilis. • This work constitutes the first study to demonstrate the antimicrobial properties of Cu-CPs against X. campestris , X. oryzae , P. piricola , A. alternata , and G. ciningulaia. The present work reports the synthesis and characterization of three Cu-based coordination polymers (CPs): [Cu(NO 3) 2 (DTP) 2 (H 2 O) 2 ] n (Cu-1), (DTP = 3,5-di(1,2,4-triazol-1-yl)pyridine), [Cu(ClO 4) 2 (DTP) 2 ] n (Cu-2), and [Cu(SO 4)(DTP)(H 2 O)] n (Cu-3). The Cu-CPs were characterized by single-crystal X-ray diffraction analysis, powder X-ray diffraction analysis, elemental analysis, infrared spectroscopy, thermogravimetric analyses, and N 2 adsorption. The anti-bacterial and anti-fungal activities of the CPs were investigated experimentally, where the materials exhibited significant inhibition ability towards three bacteria (Escherichia coli , Xanthomonas campestris , and Xanthomonas oryzae) and four fungi (Physalospora piricola , Fusarium oxysporum , Alternaria alternata , and Glomerella ciningulaia). Fluorescence microscopy, agarose gel electrophoresis for the three bacteria, and scanning electron microscopy for Alternaria alternata were further evaluated. The results suggested a slow release of Cu2+ from Cu-1 would damage the cell membrane, DNA, and mycelium of the pathogenic microorganisms. Cu-1 barely affected the growth of Bacillus subtilis. This work constitutes the first study to demonstrate the antimicrobial properties of Cu-CPs against Xanthomonas campestris , Xanthomonas oryzae , Physalospora piricola , Alternaria alternata , and Glomerella ciningulaia. [ABSTRACT FROM AUTHOR]

Two Co(II)-based coordination polymers: [Co 2 (L) 2 (bib) 2 ] n (1) and {[Co 2 (L) 2 (bimb) 2 ]·2H 2 O·DMA)} n (DMA = N,N-dimethylacetamide) (2) using 4,4′-bis(thiomethylene) dibenzoic acid (H 2 L) as the first ligand, 1,4-bis(imidazol)-butane (bib) and 1,4-bis(imidazol-1-ylmethyl)benzene) (bimb) as the second ligands, were synthesized under the condition of solvothermal and characterized by X-ray single-crystal diffraction, elemental analysis, IR spectra and thermogravimetric analysis (TGA). X-ray single-crystal diffraction analysis exhibits that 1 and 2 belong to the triclinic crystal system, space group P -1. The central Co(II) ions exhibit a regular spatial tetrahedral structure which are coordinated by two O atoms from two L2− ligands and two N atoms from two N-donor ligands. Furthermore, the photocatalytic degradation properties and mechanism of 1 and 2 for methylene blue (MB) were investigated. The results show that the band gap (E g) of 1 and 2 is 3.78 eV and 3.82 eV, and the equipotential point (pH pzc) of 1 is 4.25. Both 1 and 2 show excellent photocatalytic degradation for MB. •OH is the main active substance causing MB degradation. The photocatalytic degradation for MB of 1 and 2 is in line with the first order kinetics equation. The pH pzc of complex 1 is 4.25. When pH < 4.25, 1 has a positive charge on the surface, and will generate electrostatic repulsion with MBH2+, inhibiting the adsorption of 1 to MB, so the degradation rate of MB is greatly reduced. When pH > 4.25, complex 1 has a negative charge on the surface and generates electrostatic attraction with MBH2+, which promotes the adsorption of 1 to MB, so the degradation rate of MB is greatly increased. Image 1 [ABSTRACT FROM AUTHOR]

• Two substituted benzyl triphenylphosphinium picrate salts were synthesized and characterized. • The FT-IR and Raman spectra have been discussed and assigned. • The HOMO-LUMO energy gap explains the charge transfer interactions in the molecules. • The nonlinear optical properties were studies using DFT calculations. • The title crystals exhibit violet and green fluorescence emissions in solid state at room temperature. Two new organic hybrid materials, namely, 4-chlorobenzyl triphenylphosphinium picrate and 4-iodobenzyl triphenylphosphinium picrate [4ClBzTPP][PIC](1) and [4IBzTPP][PIC](2), have been grown by slow evaporation solution growth technique and characterized by elemental analysis, spectroscopy, thermal analysis, powder and single crystal XRD. Two new picrates crystallize in triclinic space group P −1 and consist of a pair of [4ClBzTPP]+/[4IBzTPP]+ cations and picrate anions. The one-dimensional anionic chain are constructed by the non-bonded O···O and N···O interactions. Experimental vibrational bands (IR and Raman) have been discussed and assigned. The HOMO-LUMO energy gap explains the charge transfer interactions in the molecules. TG-TDA technique reveals that two materials were stable up to 215 °C and 253 °C, respectively. Excited by 250 nm ultraviolet light, two materials emit main luminescent emissions bands at about 374 nm and 524 nm in solid state at room temperature. In addition, two picrates show good antibacterial activities against Escherichia coli and Staphylococcus aureus. The results of DFT calculations based on the structures of 1 and 2 indicate that the first hyperpolarizability value (β tot) of two crystals are 5.8 and 32.3 times that of KDP, respectively, which show good nonlinear optical properties. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Two new zinc(II)–triazole–aliphatic dicarboxylate coordination polymers, [Zn(trz)(Hsuc)] n (1), [Zn2(trz)2(tar)] n (2), have been hydrothermally synthesized by reaction of Zn salt, Htrz with H2suc and H2tar, respectively (Htrz=1,2,4-triazole, H2suc=succinic acid, H2tar=tartaric acid). Their structures were determined by single-crystal X-ray diffraction analyses and further characterized by X-ray powder diffraction, elemental analyses, IR spectra and TG analyses. Compound 1 displays a 2D layer structure containing {[Zn4(trz)4]4+} n layers decorated by the suc ligand. Compound 2 is in a 3D structure formed by the interconnection of 2D {[Zn4(trz)4]4+} n layers with tar ligand, resulting a 3,4-connected topological network. Due to the different coordination mode and conformation of aliphatic carboxylate ligand, the similar 2D {[Zn4(trz)4]4+} n layers stack in the –AAA– fashion in 1, while the {[Zn4(trz)4]4+} n layers hold together in the –ABAB– stacking sequence in 2. Additionally, the two compounds show strong fluorescence in the solid state at room temperature. [Copyright &y& Elsevier]

Abstract: Coordination polymers containing lanthanides with tartaric acid [Ln2(C4H4O6)3(H2O)3]·1.5H2O (Ln=La, Ce, Pr, Nd, Sm and C4H4O6 = d(−) or l(+) tartrate anion) have been synthesized using hydrothermal techniques and characterized by single crystal X-ray diffraction. The compounds are all isotypic with a monoclinic crystal system in the P21/n space group. The asymmetric units of coordination polymers contain two metal centers having different coordination environments. One metal is bonded to four tartrate groups having three d and one l isomers (or three l and one d isomers), whereas the other metal is bonded to five tartrate groups having two d and three l isomers (or two l and three d isomers). Each trivalent metal center is coordinated to nine oxygen atoms that originate from carboxylate and hydroxyl groups of the tartrate anions and water molecules. These new polymers have three-dimensional structures containing open channels that are occupied by non-coordinating water molecules. Thermogravimetric and differential thermal analyses and adsorption of nitrogen have also been studied for these compounds. [Copyright &y& Elsevier]