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A new Tb(III) complex based on 3‐pyridylacetic acid, [Tb(H(3‐PAA)2)(NO3)2] (1, 3‐PAA=3‐pyridylacetic acid), has been triumphantly prepared and structurally characterized. Complex 1 is a 1D chained structure linked by carboxylate groups of the 3‐PAA ligand, and its 2D supramolecular packing is controlled mainly by hydrogen‐bonds. The compound exhibits outstanding thermal stability and excellent stability under ethanol solutions. Moreover, compound 1 shows a strong solid‐state green‐emitting emission at room temperature, which demonstrates that the ligand can effectively sensitize the emission of the Tb(III) ion, and it can serve as a responsive sensing material for detecting the Fe3+ ion in ethanol solutions. [ABSTRACT FROM AUTHOR]

Multifunctional materials with a coexistence of proton conduction properties, single–molecule magnet (SMM) behaviors and magneto–optical Faraday effects have rarely been reported. Herein, a new pair of Cu(II)–Dy(III) enantiomers, [DyCu2(RR/SS–H2L)2(H2O)4(NO3)2]·(NO3)·(H2O) (R–1 and S–1) (H4L = [RR/SS] –N,N′–bis [3–hydroxysalicylidene] –1,2–cyclohexanediamine), has been designed and prepared using homochiral Schiff–base ligands. R–1 and S–1 contain linear Cu(II)–Dy(III)–Cu(II) trinuclear units and possess 1D stacking channels within their supramolecular networks. R–1 and S–1 display chiral optical activity and strong magneto–optical Faraday effects. Moreover, R–1 shows a zero–field SMM behavior. In addition, R–1 demonstrates humidity– and temperature–dependent proton conductivity with optimal values of 1.34 × 10−4 S·cm−1 under 50 °C and 98% relative humidity (RH), which is related to a 1D extended H–bonded chain constructed by water molecules, nitrate and phenol groups of the RR–H2L ligand. [ABSTRACT FROM AUTHOR]

Two new complexes based on the 2,6-dicarboxy-4-hydroxypyridine ligand, formulated as [NaCu2(CAM)(HCAM)(H2O)]·H2O (1) and [Mn(HCAM)(bim)] (2) (H3CAM = chelidamic acid or 2,6-dicarboxy-4-hydroxypyridine, bim = 2,2′-biimidazole), were synthesized. The two compounds were characterized via their IR spectra, thermogravimetric analysis, powder X-ray diffraction and single-crystal X-ray diffraction. Compound 1 features a 1-D zigzag chain constructed by μ2-κO1:κO2:κO3:κN1 HCAM2− and μ2-κO6:κO8:κO10:κN2 CAM3− ligands and Cu(II) ions. Complex 2 also shows a 1-D zigzag chain connected by μ2-κO6:κO7:κO8:κN2 HCAM2− ligands, Mn(II) ions and terminal H2bim ligands. Both complexes are further linked via H-bonding interactions to form 3-D supramolecular networks. Complexes 1 and 2 display a relatively high proton conductivity (σ) values of 6.72 × 10−5 and 1.70 × 10−4 S cm−1, respectively, at 85 °C under 100% relative humidity (RH). Notably, although complexes 1 and 2 possess similar structures with 1-D chains, the proton conductivity of 2 is higher than that of 1 because complex 2 has a higher proton density and richer hydrogen bonds stemming from two undeprotonated imidazole rings of the H2bim molecules. This work revealed that increasing the proton density of a material by incorporating proton-rich-carriers as auxiliary ligands is an effective strategy to achieve high-performance non-porous coordination polymer-based proton conductors. [ABSTRACT FROM AUTHOR]

A new family of lanthanide complexes based on a tetrazole-1-acetate ligand and a 1,10-phenanthroline co-ligand were synthesized and characterized by IR spectroscopy, thermogravimetric analyses, powder X-ray diffraction and single-crystal X-ray diffraction, and their formula is [Ln2(μ-Cl)2(1-tza)2(phen)4](ClO4)2 [Ln = Eu (1), Tb (2), Gd (3), Dy (4); 1-Htza = tetrazole-1-acetate, phen = 1,10-phenanthroline]. They show dinuclear structures bridged by mixed μ-COO−1-tza and μ-Cl−. The solid-state luminescence emission properties of 1 and 2 exhibit the characteristic emission bands of Ln cations with a lifetime of 1.49 ms and 0.20 ms, respectively. Magnetic studies reveal that 3 shows a magnetocaloric effect with −ΔSmmax = 18.5 J kg−1 K−1 at 3 K for ΔH = 5 T and 4 displays a single-molecule magnet behaviour with Ueff of 15.19 K. [ABSTRACT FROM AUTHOR]

Crystalline molecular materials exhibiting both proton conduction and single-molecule magnet (SMM) behavior would offer great opportunities for applications in fuel cell, molecular spintronic, and high-density data storage technologies. However, such kinds of materials have rarely been reported. Herein, the first example of a mononuclear proton-conductive DyIII-SMM, namely [Dy(H2bim)2(H2O)2(NO3)2](NO3) (1) (H2bim = 2,2′-biimidazole), was synthesized and characterized. Complex 1 displays high proton conductivity (σ) of 1.16 × 10−3 S cm−1 at 35 °C and 100% relative humidity (RH). The 1D H-bonding network, with 2,2′-biimidazole and coordinated water molecules acting as H-bonding donors and nitrate anions (NO3−) acting as H-bonding acceptors, plays a dominant role in allowing this high conductivity. Magnetic studies indicated that complex 1 exhibits single-ion magnet behavior. [ABSTRACT FROM AUTHOR]

A new pair of multifunctional Zn(II)–Yb(III) complex enantiomers based on a chiral amine-phenol ligand, [YbZn2(SS/RR-L)2(H2O)4](ClO4)3·5H2O (S-1 and R-1) [H2L = (SS/RR)-cyclohexane-1,2-diylbis(azanediyl)-bis(methylene)-bis(2-methoxyphenol)], were synthesized and structurally characterized. In S-1 and R-1 , the linear Zn(II)–Yb(III)–Zn(II) metal core is bridged by the phenolate oxygen atoms. Enantiomers S-1 and R-1 show chiroptical activity. Complex S-1 exhibits second-harmonic generation (SHG) and YbIII characteristic emissions in the near-infrared (NIR) region. Magnetic studies indicate that S-1 shows single-molecule magnet (SMM) behaviour. Moreover, S-1 displays a high proton conductivity of 1.55 × 10−4 S cm−1 at room temperature under 100% relative humidity (RH), which results from a 1D H-bonded chain constructed by NH groups of the chiral amine-phenol ligand, water molecules and perchlorate anions (ClO4−). The combination of these five-functions, including chiral, nonlinear optical, magnetic, luminescent and proton-conductive properties, in molecule-based materials may provide great potential for application in smart multifunctional devices. [ABSTRACT FROM AUTHOR]

A new 3-D Mn(II)-organic extended framework with a 1,4-naphthalenedicarboxylate ligand, [Mn(1,4-DNC)(DMA)]n(1), was obtained by the solvothermal reaction of MnCl2⋅4H2O and 1,4-naphthalenedicarboxylate (1,4-H2DNC) in dimethylacetamide organic solvents. Each Mn(II) atom is five-coordinated in a triagonal–bipyramidal coordination environment by four carboxylate O atoms from four different 1,4-DNC2–ligands and one O atom from a terminal DMA molecule. The neighboring Mn(II) atoms are doubly bridged by 1,4-DNC2–ligands to give a one-dimensional coordination polymeric chain [Mn(COO)2]n, and each chain is connected to four other different chains through µ4-kO1:kO2:kO3:kO4 1,4-DNC2–ligands to form a 3-D network of1. [ABSTRACT FROM AUTHOR]

Four Ln-NDC coordination polymers [ Ln(NDC)(HNDC)(H2O)] ( Ln = La ( 1), Pr ( 2), Nd ( 3), Sm ( 4), H2NDC = 1,4-naphthalenedicarboxylic acid) were hydrothermally synthesized and structurally characterized by elemental analyses, IR spectroscopy, and single-crystal X-ray diffraction. Compounds 1- 4 are isomorphous, and their structures display a layer constructed from a Ln-organic chain and NDC2- ligand, in which the H2NDC ligands adopt two different acidity-dependent types and coordination modes: HNDC1- with μ-η1:η1 and NDC2- with μ-η1:η2:η1:η2. The 3D supramolecular networks of 1- 4 are mainly controlled by hydrogen bonds interactions. The magnetic susceptibilities of complexes 2- 4 reveal overall antiferromagnetic interactions between the LnIII ions. In addition, thermogravimetric analysis of compound 2 is described. [ABSTRACT FROM AUTHOR]

Four novel Ln-bpdc coordination polymers [Ln(bpdc)(NO 3 )(DMA) 2 ] [Ln = La( 1 ), Pr( 2 ), Sm( 3 ), Eu( 4 )] [Ln = lanthanide, H 2 bpdc = 4,4-biphenyldicarboxylate acid and DMA = dimethylacetamide] have been solvothermally synthesized and structurally characterized by elemental analyses, IR spectra and single-crystal X-ray diffraction. 1 – 4 crystallize in the monoclinic space group P 2 1 / c and show a 2-D layer constructed from 1-D Ln–organic chain and tetradentate bpdc 2 − ligand. The magnetic behavior of 2 – 4 has been investigated. The solid-state photoluminescent measurement illustrates that Eu( 4 ) displays the strong fluorescent emissions, which demonstrate that π -rich aromatic organic bpdc 2 − ligands can efficiently transfer energy to the Eu III ions. In addition, thermogravimetric analysis of Pr( 2 ) is also described. [ABSTRACT FROM AUTHOR]

Eight unprecedented Ln-NDC coordinationpolymers with BBI as templates{[HBBI][Ln(NDC)2(H2O)]·H2O [Ln= La (1), Pr (2)], [HBBI]2[Sm(NDC)2(H2O)]2·1/2H2O (3), and [HBBI][Ln(NDC)2(H2O)] [Ln =Eu (4), Gd (5), Tb (6), Dy(7), Er (8)] [Ln = lanthanide, H2NDC = 1,4-naphthalenedicarboxylic acid, BBI = bis(2,2′-biimidazole)]}have been hydrothermally synthesized and structurally characterizedby elemental analyses, IR spectra, and single-crystal X-ray diffraction.Complexes 1–8crystallize in themonoclinic space group P21/cand display similar (8,8)-connected 3-D frameworks with differentdinuclear Ln secondary building units due to the effect of Ln contractionand diverse coordination modes of NDC2–ligands.As the ionic radii of Ln ions decrease, the coordination numbers ofLn ions decrease from 10, to 9, to 8. The variable-temperature magneticproperties of 2–8have been investigated.The strong fluorescent emissions of 4demonstrate thatligand-to-EuIIIenergy transfer is efficient. In addition,thermogravimetric analyses and optical diffuse reflectance spectraof these compounds are also described. [ABSTRACT FROM AUTHOR]

A novel 2-D heterometal-organic coordination polymer [AgCu2(C7H2NO5)(C7H3NO5)]n·2nH2O, obtained by a hydrothermal reaction, exhibits a (44) topology and good third-order nonlinear optical and magnetic properties, which may be a good candidate for NLO and magnetic multifunctional materials. [ABSTRACT FROM AUTHOR]

Five novel Ln-1-tza (tetrazole-1-acetic) coordination polymers have been solvothermally synthesized. Complexes Nd(1), Sm(2), Eu(3), Tb(4), Dy(5) are isomorphous, which display a dinuclear structure constructed by nitrate-O-bridged and μ 1,3 carboxyl groups from 1-tza ligand. Variable-temperature magnetic studies reveal that complexes 1 – 5 exhibit antiferromagnetic interactions between lanthanide cations. Photoluminescence studies show that complexes Eu(3) and Tb(4) possess strong luminescence, and compound Nd(1) show characteristic emissions in the near-infrared region. • Five new dinuclear lanthanide complexes based on tetrazole-1-acetic were obtained. • The five complexes are antiferromagnetic interactions. • Eu(3) and Tb(4) possess strong luminescence in the visible region. • Nd(1) shows characteristic emissions in the near-infrared region. Five new lanthanide complexes based on tetrazole-1-acetic ligand and 2,2′-bipyridine as auxiliary ligand have been solvothermally synthesized with the formulas [Ln 2 (1-tza) 2 (NO 3) 4 (2,2′-bipy) 2 ] [Ln = Nd (1), Sm (2), Eu (3), Tb (4), Dy (5), 1-tza = tetrazole 1-acetic and 2,2′-bipy = 2,2′-bipyridine] and structurally characterized by elemental analyses, IR spectra and single-crystal X-ray diffraction. The single-crystal X-ray diffraction data reveal that complexes 1 – 5 are dinuclear structures constructed by nitrate-O-bridged and μ 1,3 carboxyl groups from 1-tza ligand, in which each nine-coordinated center Ln(III) ion is in a slightly distorted capped square antiprism geometry. The magnetic behaviors of 1 – 5 have been investigated. The solid-state photoluminescent measurements illustrate that complexes Eu 3 and Tb 4 display the strong fluorescent emissions in the visible region, whereas Nd 1 shows the characteristic near-infrared(NIR) luminescence. In addition, thermogravimetric analysis of Eu 3 is also described. [ABSTRACT FROM AUTHOR]

Abstract: Three novel Zn(II) complexes based on tetrazole-1-acetic ligand, Zn(1-tza)2(phen) (1), [Zn(1-tza)(2,2′-bipy)(H2O)]∙X (X=NO3 − 2, ClO4 − 3) (1-tza=tetrazole 1-acetic, phen=1,10-phenanthroline, 2,2′-bipy=2,2′-bipyridine), were synthesized and structurally characterized by single-crystal X-ray diffraction. Three different coordination modes of 1-tza ligand exist in the three obtained complexes. The 1-D chain of 1 is built by μ 2-1-tza bridges. Compounds 2 and 3 are isomorphous, and their structures show a 2-D (4,4)-connected net constructed from binuclear [Zn2(COO)2] unit and μ 3-1-tza linkers. Photoluminescence studies show that 1, 2 and 3 exhibit strong luminescence. The thermal analyses of the three complexes and the optical properties of 1 and 3 have also been investigated. [Copyright &y& Elsevier]