Synthesis,Crystal Structure,and Luminescent Properties of Ag(I) Coordination Polymer with Tricarboxylic Acid and Flexible N-donor Ligand

The reaction of AgNO₃ with combinations of 1,3-bis(4-pyridyl)propane (bpp) and 1,3,5-benzenetricarboxylic acid (H₃btc) in aqueous alcohol/ammonia at room temperature produces crystals of {[Ag₆(H₂O)₂(bpp)₆] · (btc)₂ · 25H₂O} _n (Ι). Single crystal X-ray diffraction analysis reveals that the complex Ι consists of 1D infinite cationic chains of [Ag(bpp)] _n ⁿ⁺ and [Ag(H₂O)(bpp)] _n ⁿ⁺ which are further linked into the cation layer of [Ag(bpp)] _n ⁿ⁺ by Ag···π interactions. The noncoordinated btc^3? serves as template driving surrounding water molecules to aggregate into the anionic water layer. The neighboring anionic water layer and cationic layer were further alternately joined into a 3D sandwich-like framework by hydrogen bonding. In addition, the luminescent properties of Ι were investigated.     

Self-assembly of a Cd(II) coordination polymer with the 3,5L2 topology: Synthesis,structure, and properties

A new cadmium(II) coordination polymer, [Cd(ntdc)(dps)·H₂O]_n, was synthesized using 3-nitro-thiophene-2,5-dicarboxylic acid (H₂ntdc) and 4,4´-dipyridylsulfide (dps) as organic linkers. In the complex, adjacent Cd²⁺ ions are linked by ntdc^2? anions adopting a new coordination mode to form a one-dimensional (1D) [Cd(ntdc)]_n chain. Then dps ligands further expand the 1D chain into a corrugated two-dimensional (2D) layer network by linking neighboring Cd²⁺ ions. Topologically, the 2D network can be rationalized to a 3,5-connected 3,5L2 topology. Moreover, solid state properties such as thermogravimetric analysis and photoluminescent property were also investigated.     

Synthesis and crystal structure of a 2D (6,3) coordination network, {[Ag(L)1.5]NO3} n [L = 1,3-bis(benzylthio)propane]

A new dithioether silver(I) complex, {[Ag(L)_1.5]NO₃} _n (1) has been prepared by the reaction of AgNO₃ with 1,3-bis(benzylthio)propane (L) in methanol/chloroform. The structure was characterized by single-crystal X-ray diffraction analysis: rhombohedral system, space group R –3c, with a =b = 15.651(7), c = 39.26(4) Å, V = 8328(1) ų, and Z = 6. The crystal structure consists of [Ag(L)_1.5]⁺ cations and NO₃ ^– anions. In 1, each silver(I) center is coordinated equivalently to three sulfur donors from three different ligands to give a trigonal-planar coordination geometry. Each L links two adjacent silver(I) centers in bis-monodentate bridging mode to form a 2D (6,3) network sheet. Furthermore, these 2D sheets are linked by the weak coordination interactions between nitrate ions and silver(I) atoms to form a 3D brick-wall framework.     

A two-dimensional Zn(II) coordination polymer with a three-dimensional supramolecular architecture comprising 5-dimethylamino-isophthalic acid and 1,3-bis(4-pyridyl)propane

A new zinc coordination polymer, [Zn(L)(bpp)·H₂O]_n, was synthesized using 5-dimethylamino-isophthalic acid (H₂L) and 1,3-bis(4-pyridyl)propane (bpp) as organic linkers. In the complex, adjacent Zn²⁺ ions are linked by L^2? anions to form a one-dimensional (1D) [ZnL]_n chain. Then bpp ligands expand the 1D chains into a corrugated two-dimensional (2D) layer network by linking neighboring Zn²⁺ ions. These adjacent layers are further stacked together by direct C?H···π supramolecular interactions, generating a three-dimensional (3D) supramolecular structure. From the viewpoint of topology, the 2D network can be rationalized to a uninodal four-connected non-interpenetrated sql/Shubnikov tetragonal plane net with {4⁴.6²} topology. Moreover, the solid state properties such as thermogravimetric analysis and luminescence were also investigated.     

Synthesis and Crystal Structure of a 1D Silver(I) Complex {[Ag (<Emphasis Type="Bold">L</Emphasis>)(CH<Subscript>3</Subscript>CN)](ClO<Subscript>4</Subscript>)}<Subscript>n</Subscript> [<Emphasis Type="Bold">L</Emphasis> = 5,6-dicyano-2,3-di(2-pyridyl)pyrazine]

Abstract The reaction of the organic ligand, 5,6-dicyano-2,3-di(2-pyridyl)pyrazine (L) with AgClO₄, leads to the formation of a novel complex {[Ag(L)(CH₃CN)](ClO₄)}n 1, which has been characterized by elemental analysis, IR and single-crystal X-ray diffraction analysis (monoclinic system, space group P2(1)/n, with a = 11.290(4), b = 12.660(5), c = 15.202(6) ?, β = 90.141(6)°, V = 13371(2) ?³ and Z = 4). The crystal structure of complex consists of polymeric chains of {[Ag(L)(CH₃CN)]⁺}n cations and anions. In the cation of 1, each Ag(I) center is coordinated to four N atoms from two symmetry-equivalent L ligands and a CH₃CN molecule. The adjacent two Ag(I) ions are linked by L ligands which adopt N₃-coordinated bridging mode to form a zig-zag chain. Index abstract Synthesis and Crystal Structure of a 1D Silver(I) Complex {[Ag (L)(CH₃CN)](ClO₄)}_n [L = 5,6-dicyano-2,3-di(2-pyridyl)pyrazine] Qian Gao, Ya-Bo Xie*, Sha Chen, and Dao Wang The crystal structure of complex {[Ag(L)(CH₃CN)](ClO₄)}_n (L = 5,6-dicyano-2,3-di(2-pyridyl)pyrazine) consists of polymeric chains of {[Ag(L)(CH₃CN)]⁺}_n cations and anions. Each Ag(I) center is coordinated to four N atoms from two symmetry-equivalent ligands and a CH₃CN molecule. The adjacent two Ag(I) ions are linked by ligands which adopt N₃-coordinated bridging mode to form a zig-zag chain.      

Growth mechanism of crystals from aqueous solutions

Microscopic processes occurring on the surface of a growing crystal or a dissolving one were observed by microcinematography. The crystals under observation were grown either in a drop of solution by evaporation or in a constant-temperature microscope stage at a chosen supersaturation. Small (approx. 0.1 mm) and large (approx. 10 mm) crystals of NaCl, Pb(NO₃)₂, NaNO₃, CdI₂, KDP and ADP were studied. It is concluded qualitatively that the layers, in general polygonal, originating in one or several active centres, are formed on the crystal face, never at the corners or edges. – The average velocity of layer motion was studied quantitatively in dependence on their thickness and supersaturation. The layer motion at constant supersaturation considerably fluctuated. – Surface patterns created by moving layers agree in most cases with predictions of the dislocation theory. Two categories of steps were found on the surface: ”︁real”︁ macrosteps and shock waves. – The velocity of layer motion for most compounds lies within (1–10) · 10⁻⁴ cm · s⁻¹.     

Construction of one new two-dimensional Zn(II) coordination polymer based on thiophene-2,5-dicarboxylate and bis(imidazole) mixed ligand

Under hydrothermal conditions, a new two-dimensional (2D) zinc coordination polymer, [Zn(tdc)(bimm)]_n, was synthesized based on thiophene-2,5-dicarboxylic acid (H₂tdc) and 1,2-bis(imidazol-1′-yl)methane (bimm) mixed ligands. Single crystal X-ray structural analysis shows adjacent Zn²⁺ ions are connected by tdc^2? anions to form a one-dimensional (1D) [ZnL]_n chain in the complex. Then flexible bimm ligands expand 1D chains into a 2D layer by linking neighboring Zn²⁺ ions. These adjacent layers are further stacked together by direct C?H···π supramolecular interactions, generating a double-layer 2D supramolecular structure. In topology, the 2D lay could be rationalized to a uninodal 4-connected non-interpenetrated sql net with {4⁴.6²} topology. In addition, solid state properties such as thermogravimetric analysis and luminescence were also investigated.     

Crystal structure and spectroscopic studies of a new organic monohydrogenmonophosphate dihydrate

The crystal synthesis and structure of a new organic monohydrogenmophosphate (3,4‐Cl₂‐CH₂C₆H₃NH₃)₂HPO₄·2H₂O are reported. This compound crystallizes in the monoclinic P2₁/n with a = 9.081(7) Å, b = 6.501(5) Å, c = 35.423(12) Å, β = 91.09(5)°, V = 2090.9(2) ų, and Z = 4. Crystal structure was solved and refined to R = 0.042, using 2543 independent reflections. It can be described by inorganic layers, including the HPO₄^‐ anions and the H₂O molecules, parallel to (a, b) planes and situated at z = 0 and z = 1/2. The interlayer spacing is occupied by the organic molecules which perform different interactions around the 3D network cohesion. A characterization of this compound by solid‐state (¹³C, ³¹P) MAS NMR and IR spectroscopies is also reported. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Synthesis and Crystal Structure of a Cyano-Bridged Bimetallic Nickel(II)–Silver(I) Complex, [Ni(dmen)<Subscript>2</Subscript>{Ag(CN)<Subscript>2</Subscript>}<Subscript>2</Subscript>] · 0.5H<Subscript>2</Subscript>O

A cyano-bridged heteronuclear bimetallic complex [Ni(dmen)₂{Ag(CN)₂}₂] · 0.5H₂O (dmen = N,N′-dimethylethylenediamine) has been prepared and characterized by IR spectroscopy and X-ray Crystallography. The compound crystallizes in the monoclinic space group P2₁/c. The crystal structure of the complex consists of two independent centrosymmetric trinuclear molecules made up of a [Ni(dmen)₂] ⁺² unit linked to two [Ag(CN)₂]⁻ anions in a trans configuration. The trinuclear units are joined by hydrogen bonding to form irregular chains.     

A new Pb<Superscript>II</Superscript>(ethylenediaminetetraacetate) coordination polymer with a two-dimensional layer structure

A new Pb^II?edta^4– coordination polymer, Pb₂(edta)(H₂O)_0.76 (edta^4– = ethylenediaminetetraacetate) was synthesized under hydrothermal condition. Single crystal X-ray analysis reveals that it represents a novel two-dimensional (2D) Pb²⁺–edta^4– layer structure with a (4,8²)-topology. Each edta^4– ligand employs its four carboxylate O and two N atoms to chelate one Pb^II atom (hexa-coordinated) and connects five Pb^II atoms (ennea-coordinated) via its four carboxylate groups to form 2D layer framework. Adjacent layers are packed into the overall structure through vander Waals interactions.     

Efficient and practical method for the synthesis of hydrophobic azines as liquid crystalline materials

A series of hydrophobic symmetrical azines: 1,2-bis[4-(n-alkoxy)benzylidene]hydrazine (where, n-alkoxy: O(CH₂)_nH, n = 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 16, or 18) have been prepared following an efficient and practical method. These compounds have been synthesized via the condensation reaction of hydrazine hydrate and appropriately 4-(n-alkoxy) benzaldehydes in acidic medium under ambient conditions. The prepared organic compounds have been characterized and their structures were elucidated depending upon micro-elemental analysis and spectral data (IR, UV-Vis, ¹HNMR, ¹³C{¹H}NMR, 2D ¹H-¹H-cozy, 2D ¹H-¹³C-HSQC, and mass spectra). Liquid crystalline behavior of the prepared compounds was studied using polarized light optical microscopy and differential scanning calorimetry techniques. This study revealed that all the compounds displayed enantiotropic liquid crystal properties, exhibiting smectic and nematic mesophases.     

Polycrystalline Synthesis and Single Crystal Growth of AgGaS2

A modified two temperature vapor transport procedure has been used to synthesize AgGaS₂ polycrystalline materials at 1060 °C from high-purity Ag, Ga, S elements. The results showed that the polycrystalline materials are pure single phase AgGaS₂ by X-ray powder diffraction analysis. The polycrystalline ingot includes a few interior voids and has a high mass density. The AgGaS₂ ingot with 12 mm in diameter and 20 mm in length has been grown by the modified Bridgman technique in two-zone vertical furnace. As-grown AgGaS₂ ingot was characterized by the X-ray diffraction technique, obtained the rocking curve of the crystal (011) face, it is shown that the ingot is AgGaS₂ single crystal. The infrared transparent of the crystal at 2 ∼ 10μm is 49% (and absorption coefficient is 0.74 cm^—1).     

pH‐Controlled topologies of two Co(II) complexes based on 5‐Nitro‐1,2,3‐benzenetricarboxylic acid and 1,6‐Bis(1,2,4‐triazole‐1‐yl)hexane

Two new Co(II) coordination polymers, [Co(Hnbta)(bth)]_n ( 1 ) and {[Co₃(nbta)₂(bth)₃(H₂O)]·H₂O}_n ( 2 ), (H₃nbta = 5‐nitro‐1,2,3‐benzenetricarboxylic acid and bth = 1,6‐bis(1,2,4‐triazole‐1‐yl)hexane), have been synthesized under different pH values through hydrothermal reactions. Both complexes were characterized by elemental analysis, IR spectra, thermogravimetric analysis (TGA), and single‐crystal X‐ray crystallography. Complex 1 exhibits a 3D polythreaded network based on 4‐connected sql 2D layer. Complex 2 has a (4,4,5)‐connected trinodal 3D pillar‐layered network with a (4²·6⁴)₂(4²·6⁷·8)₂(6⁴·8²) topology. Magnetic susceptibility measurements indicate that complexes 1 and 2 show weak antiferromagnetic interactions between the adjacent Co(II) ions.     

Stimulated Raman scattering by C<Subscript>12</Subscript>H<Subscript>22</Subscript>O<Subscript>11</Subscript> sugar (sucrose)

The efficient Stokes and anti-Stokes laser emissions with Raman frequency shift at about 2960 cm^?1 are excited in a food C₁₂H₂₂O₁₁ sugar (sucrose) single crystal under pulsed pumping. Other (χ⁽²⁾ + χ⁽³⁾) effects of the parametric Raman generation are also detected.     

A new photoluminescent supramolecular inorganic‐organic hybrid zincophosphate complex pillared by carboxylate ligand through hydrogen bonding interactions

A new inorganic‐organic hybrid zincophosphate, [Zn(H₂O)₂(H₂PO₄)₂]·2PABA ( 1 ) (PABA = p‐aminobenzoic acid), pillared by PABA ligands through hydrogen bonding interactions, has been synthesized and characterized. Single‐crystal X‐ray diffraction reveals that 1 crystallizes in the monoclinic P 2₁/c space group. The geometric feature in 1 is the 3D supramolecular structure constructed from alternately arranged organic and inorganic layers that consist of infinite parallel inorganic chains. These chains are extended to a 2D inorganic layer through intermolecule hydrogen bonding interactions between N atoms (from PABA ligand) and two O atoms (from adjacent inorganic chains). 1 was characterized by IR spectroscopy, XRD, DSC/TGA. The fluorescent property for 1 in solid state was also investigated at room temperature. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Zur Realstruktur von Ga1–xInxAs LPE-Schichten

Ga_1–xIn_xAs epitaxial layers (0.02 ≦ × ≦ 0.12) are grown on (111)-oriented GaAs substrates from nonstoichiometric melts. The etch pit densities – determined by chemical etching – yield values between 2 · 10⁵ cm⁻² and 3 · 10⁷ cm⁻² and were found to be dependent on composition, layer thickness and cooling rate. X-ray topography of cleaved {110}-planes gives information on layer quality and indicates the existence of stress in the substrate lattice near the heterojunction. The validity of Vegard's law in the investigated concentration range was confirmed by X-ray determination of the lattice constants. The half width of double crystal spectrometer rocking-curves, the epd and the relative intensity of photoluminescence show similar dependence on the composition of the mixed crystal layers.     

Crystal growth,structure and spectroscopic studies of a novel organic single crystal: L‐lysine p‐nitrophenolate monohydrate (LLNP)

A novel organic crystal, L‐lysine p‐nitrophenolate monohydrate (LLNP) has been grown successfully from an aqueous solution by the slow cooling method. Transparent single crystal of dimensions 22 × 12 × 12 mm³ has been obtained. The single crystal X‐ray diffraction has shown that LLNP belongs to the orthorhombic crystallographic system with space group P2₁2₁2₁. The functional groups and vibrational frequencies of the crystal have been identified using IR and Raman spectra. The proton and carbon configurations have been confirmed through ¹H‐NMR and ¹³C‐NMR spectra analyses. The UV‐Vis‐NIR transmittance spectrum for LLNP crystal has been recorded in the range from 200 to 2500 nm. The second harmonic generation (SHG) intensity of LLNP has been measured by powder SHG method and found to be as 4.2 times as that of KDP. The thermal properties have been studied by using thermo gravimetric (TG) and differential thermal analysis (DTA).     

Two Ag(I)-Containing Supramolecular Coordination Polymers Constructed from the Multidentate N-donor Ligand 1-((1H-1,2,4-triazol-1-yl)methyl)-3,5-bis(3-pyridyl)-1,2,4-triazole Based on Hydrogen-Bonding and π–π Interactions: Syntheses,Crystal Structures,Optical Band Gaps and Luminescent Properties

Two Ag(I)-based coordination polymers, namely [Ag₂(3,3′-tmbpt)(o-Hbdc)₂]·H₂O (1) and [Ag₈(3,3′-tmbpt)₄(1,2,4-Hbtc)₄(H₂O)] (2) (3,3′-tmbpt?=?1-((1H-1,2,4-triazol-1-yl)methyl)-3,5-bis(3-pyridyl)-1,2,4-triazole, o-H₂bdc?=?1,2-benzenedicarboxylic acid and 1,2,4-H₃btc?=?1,2,4-benzenetricarboxylic acid), have been synthesized. Single-crystal X-ray diffraction analyses, elemental analyses, infrared spectra, powder X-ray diffraction analyses and thermogravimetric analyses have been carried out to characterize the structures of 1 and 2. Compound 1 shows a (3,4)-connected 2D layered structure with a Schläfli symbol of (4²·6)(4²·6³·8). The intermolecular O–H···O hydrogen-bonding interactions extend the 2D layer into a 3D supramolecular architecture. Compound 2 exhibits a (3,3)-connected double-layered structure with a Schläfli symbol of (4·8·10)₂(8²·10)₂. The intermolecular C–H···O hydrogen-bonding interactions link the double-layers to form a 3D supramolecular architecture. Moreover, there are intramolecular and intermolecular π–π interactions in 1 and 2, which stabilize the whole 3D supramolecular architectures. The band gaps of 1 and 2 are 3.19 and 3.09 eV, respectively, indicating the potential of 1 and 2 as semiconductive materials with wide band gaps. Moreover, 1 and 2 emit intense blue-green light, which may be potential photoactive materials.

Graphic Abstract

Two Ag(I)-based 3D supramolecular coordination polymers constructed from a multidentate N-donor ligand and two aromatic polycarboxylate anions via hydrogen-bonding and π–π interactions have been synthesized and characterized. The band gaps and photoluminescent properties of the compounds have been studied.

     

Two organic‐inorganic hybrids with Keggin polyanions

Two new Keggin polyoxometalates [Co(phen)₃]₂[SiW₁₂O₄₀]·6H₂O (1) and (ppy)₆ H₄SiMo₁₂O₄₀·0.4H₂O (2) (phen = 1,10′‐phenanthroline, ppy = 4‐(5‐phenylpyridin‐2‐yl)pyridine) have been synthesized by the hydrothermal method. Single crystal X‐ray analysis revealed that compound 1 crystallizes in the monoclinic crystal system with cell parameters of a = 13.344(2) Å, b = 17.191(3) Å, c = 22.002(4) Å, α = 90.00°, β = 99.566(2)°, γ = 90.00°, V = 4977 ų, Z = 2, and compound 2 crystallizes in the triclinic crystal system with cell parameters of a = 11.297(2) Å, b = 12.341(3) Å, c = 19.354(4) Å, α = 107.60(3)°, β = 95.80(3)°, γ = 94.16(3)°, V = 2543.7(9) ų, Z = 1. Both 1 and 2 represent organic ligand molecules and inorganic Keggin anions, which are further interconnected to a 3D framework by supramolecular interactions. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Growth and characterization of magneto‐optical YFeO3 crystals

The floating zone growth of magneto‐optical crystal YFeO₃ has been investigated. The polycrystalline feed rod was prepared by a pressure of 250MPa and sintering at about 1500°C. A crack‐ free YFeO₃ single crystal has been successfully grown. The crystal preferred to crystallize along <100> direction with about 10° deviation. The X‐ray rocking curve of the crystal has a FWHM of 24 arcsec, confirming the high crystal quality of the sample. The (100) plane was etched by hot phosphoric acid and the dislocation density was about 10⁴/cm². A thin outer layer with Y₂O₃‐rich composition was found at the periphery of as‐grown crystals, which was attributed to the Fe₂O₃ evaporation during growth. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)