Synthesis,Crystal Growth,Structural and Physical Properties of bis(thallium) bis(nitrilotriacetato) zirconate dihydrate,Tl2Zr(N[CH2COO]3)2 · 2H2O

Single crystals of Tl₂Zr(N[CH₂COO]₃)₂ · 2H₂O having optical quality and dimensions up to 30 × 25 × 12 mm have been grown from aqueous solutions by controlled lowering of temperature. The raw material was synthesized as the first fraction of crystallization during evaporation of an aqueous solution of (CH₃NH₃)₂Zr(N[CH₂COO]₃)₂ · 2H₂O and TlNH₂SO₃. A crystal structure analysis revealed an isotypy to the K₂Zr(N[CH₂COO]₃)₂ · 2H₂O family, space group Ccc2, a₁ = 14.780(2)Å, a₂ = 14.933(2)Å, a₃ = 8.901(1)Å, Z = 4, ρ_calc. = 3.145 gcm^‐3. Thermal stability, thermal expansion and pyroelectric, dielectric, piezoelectric, elastic and thermoelastic properties have been determined. All properties are closely related to those of Rb₂Zr(N[CH₂COO]₃)₂ · 2H₂O.     

The precipitation of alkaline-earth metal polymetaphosphate hydrate powders from aqueous solution. Nucleation and crystal growth processes,final precipitate compositions and crystal sizes

The precipitation of barium, strontium, calcium and magnesium polymetaphosphate hydrates was studied from aqueous solutions of initial metal salt concentrations from 0.001 to 3 M at 20 °C; equivalent sodium polymetaphosphate solutions were added to the alkaline-earth metal chloride solutions. Precipitate compositions were determined by chemical analysis, paper chromatography, potentiometric analysis, thermogravimetric and differential thermal analysis and infra-red spectrophotometry; final crystallite morphologies and sizes were studied by scanning electron microscopy and X-ray powder diffraction. Nucleation rates and nucleus numbers (at the end of the induction periods) were very high; crystal numbers varied from 10¹⁴ to 10¹⁵ at the critical concentrations to above 10¹⁷ per 1. solution. Crystal growth rates were also very high and varied as the fourth power of the initial metal salt concentration. High molecular-weight metal polymetaphosphate hydrates were precipitated from the more dilute solutions (0.001 to 0.025 M) while increasing amounts of the more soluble intermediate and low molecular-weight products were precipitated from the more concentrated solutions. Washing with cold water removed the tri- and tetralinear and cyclic phosphate products. The magnesium salts were not precipitated even from 3 M aqueous solutions. The precipitates from aqueous (NaPO₃(I))_n (n = 12) solutions had the compositions (BaP₂O₆ · 2.5 H₂O)₆, (SrP₂O₆ · 3 H₂O)_n and (CaP₂O₆ · 4 H₂O)_n while the magnesium salt precipitate from 20 percent aqueous acetone solution had the composition (MgP₂O₆ · 4 H₂O)_n, the precipitate n values varied from 19 to 13. The precipitates from aqueous (NaPO₃(II))_n (n = 20) solutions contained 0.5n to n additional adsorbed water molecules; these precipitate n values varied in turn from 40 to 26. The final precipitate powders consisted of ‘spherules’ of highly microcrystalline or amorphous polymer glass; the spherule diameters were about 0.2 μm at the critical concentrations and decreased to below 0.05 μm with increasing solution concentrations.     

Synthesis and Structure of Strontium and Barium Uranyl Methacrylates

Crystallography Reports - Synthesis, X-ray diffraction analysis, and IR spectroscopy of Sr2[UO2(CH2C(CH3)COO)3]4 · 26H2O (I) and Ba2[UO2(CH2C(CH3)COO)3]4 · 26H2O (II) (CH2C(CH3)COO?...     

The Coprecipitation of Magnesium Iron (III) Hydroxide Powders from Aqueous Solution: Precipitate Compositions and Coprecipitation and Ageing Mechanisms

Series of magnesium iron(111) hydroxides were coprecipitated at ambient temperature from different mixed metal cation solutions, at C_{M tot} = 0.1 M and Mg/Fe₂ ratios from 4 to 1/4, with sodium hydroxide solution. The relevant single precipitations and the coprecipitations were monitored by potentiometric (pH) titration and the final coprecipitate compositions were examined by chemical analysis, infra-red spectrophotometry and thermal analysis. The coprecipitates onto aged α-FeOOH were simple mixtures of α-FeOOH and Mg(OH)₂. The main coprecipitates were either «molecular inclusion mixtures» of microcrystalline α-FeOOH with excess Mg(OH)₂ or similar mixtures of Mg(OH)₂ with excess α-FeOOH and some ten-twenty percent (relative to the Mg content) of magnesium hydroxo-ferrate(III) hydrate Mg[Fe(OH)₄]₂ · h H₂O. The coprecipitates aged in alkaline magnesium hydroxide suspension at 20 °C and 40 °C were mixtures of Mg(OH)₂, α-FeOOH and forty to ninety percent (relative to the Mg content) of Mg[Fe(OH)₄]₂ · h H₂O. The related α-FeOOH NaOH and α-FeOOH Mg(OH)₂ equilibria and the different coprecipitation mechanisms are discussed.     

Syntheses and crystal structures of an organometallic thiosemicarbazone and an organometallic enehydrazide

Reactions of ferrocenoylacetone with thiosemicarbazide and isonicotinic acid hydrazide generate an organometallic thiosemicarbazone 1 and enehydrazide 2, respectively. The complexes 1 and 2, which can be formulated as [C₅H₅FeC₅H₄C(O)CH₂C(=NNHCSNH₂)CH₃] and [C₅H₅FeC₅H₄C(O)CH=C(NHNHCOC₅H₄N-4)CH₃], have been characterized by elemental analyses, IR, NMR, UV and were structurally characterized by single-crystal X-ray crystallography. Complex 1 (C₁₅H₁₇FeN₃OS) crystallizes in the monoclinic space group P2₁/c, with lattice constants: a = 13.939(3) ?, b = 8.2600(17) ?, c = 13.176(3) ?, β = 94.83(3)°, V = 1511.7(6) ?³, Z = 4, D _c = 1.508 g cm⁻³, F(000) = 712, R ₁ = 0.0602, wR ₂ = 0.1526. Two intermolecular hydrogen bonds N–H···S (N···S = 3.356(8) and 3.499(7) ?, N–H···S = 168 and 170°) form a chain in the [010] direction. The intermolecular hydrogen bond C–H···O (C···O = 3.432(10) ?, C–H···O = 151°) leads to a [010] double-chain through each unit cell. The intermolecular hydrogen bond C–H···O (C···O = 3.359(10) ?, C–H···O = 173°) makes the [010] double-chain pack along the c axis to result in a two-dimensional network. Complex 2 (C₂₀H₁₉FeN₃O₂) crystallizes in the monoclinic space group P2₁/c, with lattice constants: a = 14.091(2) ?, b = 10.024(2) ?, c = 13.806(2) ?, β = 112.41(2)°, V = 1802.8(6) ?³, Z = 4, D _c = 1.434 g cm⁻³, F(000) = 808, R ₁ = 0.0576, wR ₂ = 0.1593. The strong intramolecular hydrogen bond N–H···O from the enamine N atom and carbonyl O atom stabilizes the enehydrazide. The intermolecular hydrogen bonds N–H···O and C–H···O (N···O = 2.906(6) ?, N–H···O = 155° C···O = 3.364(6) ?, C–H···O = 153°) generate a [010] chain. The intermolecular hydrogen bond N–H···O (N···O = 2.989(6) ?, N–H···O = 128°) forms a [010] double-chain through each unit cell. The π···π stacking interation involving the pyridyl groups makes the [010] double-chain pack along the c axis to lead to a two-dimensional network.     

The crystal structure of nematogenic 2-bromo-1,4-phenylenediyl bis(trans-4-n-propylcyclohexanoate) — a special kind of disorder

The title compound with the formula C₃H₇–C₆H₁₀–COO–C₆H₃Br OOC C₆H₁₀ C₃H₇ (BPBPC) crystallizes in a triclinic unit cell with dimensions a = 5.822(2), b = 8.732(3), c = 13.016(5) Å, α = 94.42(3)°, β = 93.47(3)°, γ = 104.85(2)° containing one molecule. The structure has been solved by heavy atom method and refined to R = 0.083. The BPBPC molecules adopt an optimum stretched form and exhibit pseudo-centrosymmetry in consequence of a special kind of disorder within the crystal lattice.     

Two Isostructural Complexes Constructed from Mixed Ligands of Dipyrido[3,2-d:2′,3′-f]quinoxaline and Phthalate with Novel Oxygen Clusters

Abstract Two isostructural dinuclear complexes [M₂(Dpq)₂(phth)₂(H₂O)₄] · 2H₂O [M = Zn(1), Ni(2), Dpq = dipyrido[3,2-d:2′,3′-f]quinoxaline, phth = phthalate] have been synthesized and characterized. Crystal data: (1), Mr = 1031.55, monoclinic, C2/c, a = 27.7948(11), b = 10.5196(4), c = 15.0390(5) ?, β = 110.818(1), Z = 4, V = 4110.2 ?³, R ₁ = 0.0277, wR ₂ = 0.0718 [I > 2σ(I)]; (2), Mr = 1018.19, monoclinic, C2/c, a = 27.675(4), b = 10.3601(15), c = 15.082(2) ?, β = 110.954(2), Z = 4, V = 4038.3 ?³, R ₁ = 0.0248, wR ₂ = 0.0668 [I > 2σ(I)]. The dinuclear units are connected into 2-D supramolecular net through O–H···O hydrogen bonding. Moreover, the 2-D networks are ultimately packed into a 3-D supramolecular structure via interlayer π···π stacking interaction between the aromatic rings of Dpq ligands. Furthermore, the photoluminescence property of compound 1 is also studied. Graphical Abstract Two isostructural dinuclear complexes [M₂(Dpq)₂(phth)₂(H₂O)₄] · 2H₂O [M = Zn(1), Ni(2), Dpq = dipyrido[3,2-d:2′,3′-f]quinoxaline, phth = phthalate] have been synthesized, and the structure study reveals that each dinuclear complex is connected with six other dinuclear units through the O–H···O hydrogen bonding to form 2-D supramolecular networks.      

Synthesis and crystal structures of two new complexes [M(OH2)(HDPA)2]·3H2O (M = Mn, Co)

Two new transition metal complexes of [M(OH₂)(HDPA)₂]·3H₂O (M=Mn(1); M=Co(2)) (H₂DPA, 2,6-pyridine-dicarboxylic acid) have been prepared at room temperature from the reaction of MCl₂·6H₂O (M=Mn or Co) and H₂DPA in the mixed solvent of H₂O and EtOH in the presence of piperazine, and were characterized by X-ray analysis, elemental analysis. X-ray analysis reveals that the coordination geometries of Mn²⁺ and Co²⁺ are of octahedron and severely distorted square-based pyramid, respectively. Crystal data: [Mn(OH₂)(HDPA)₂]·3H₂O (1), Mr=459.23, monoclinic, P2(1)/n, a=7.0056(3), b=(23.8125(12), c=10.7444(3) ?, β=99.834(2)°, Z=4, V=1766.28(13) ?³, R ₁=0.0586, wR ₂=0.1448 [I>2σ(I)]; Co(OH₂)(HDPA)₂]·3H₂O (2), Mr=463.22, monoclinic, P2(1)/n, a=7.0014(2), b=23.8346(7), c=10.7212(4) ?, β=99.8540(10)°, Z=4, V=1762.71(10) ?³, R ₁=0.0474, wR ₂=0.1366 [I>2σ(I)].     

A novel Zn(II) coordination polymer based on tetra-carboxylates ligand and N-donor ligand: synthesis,structure and photocatalytic properties

Abstract

Novel film polymeric composites based on the non-photoconducting polyvinyl butyral with heterometallic complexes (NH₄)_4n{[Cu(en)(H₂O)][P₂Mo₅O₂₃]}_n·3.5nH₂O (1) and (NH₄)_2n{[Cu(en)₂][Cu(en)(H₂O)][P₂Mo₅O₂₃]}_n·3nH₂O (2) [en?=?ethylenediamine] have been prepared. Both compounds are similar and contain Strandberg anions [P₂Mo₅O₂₃]^6– linked to Cu-diamine species. The main structural difference between complexes is the presence of additional bridging [Cu(en)₂] fragments in 2, which provide an extra connectivity between the neighboring polyoxometalates. However, the different saturations and relaxation times of the photoresponse, as well as different activation energies, are shown. The variability of the photoconducting properties can be explained by the influence of a chain rigidity on the transport of non-equilibrium charge carriers.     

Self‐assembly synthesis and structure of mono‐ and di‐nuclear uranyl complex

Mixing the malonate (mal), 4,4′‐bipyridine, UO₂(CH₃COO)₂ · 2H₂O in different solvent condition gets two compounds (bpy)₂(H₂bpy)[UO₂(mal)₂(μ‐H₂O)] · 8H₂O (1) and (H₂bpy)[UO₂(mal)₂] · 2H₂O (2) . Both complexes contain seven‐coordinated pentagonal bipyramidal uranium center. Crystal 1 is mononuclear structure and crystal 2 contains dinuclear [(UO₂)₂(mal)₂(μ₂‐mal)₂]^4‐ subunit. Particularly, Crystal 2 forms the twodimensional supramolecular topology by hydrogen bonds. The sheet constructs from two sorts of chamber, of which the larger one has two water molecular guests. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

The Double Salts Cd(C6H5COO)2 · CdCl2 and Cd(C6H5COO)2 · CdBr2

The systems Cd(C₆H₅COO)₂ CdCl₂ H₂O and Cd(C₆H₅COO) ₂ CdBr₂ H₂O have been studied at 25 °C. Formation of the double salts Cd(C₆H₅COO)₂ · CdCl₂ and Cd(C₆H₅COO)₂ · CdBr₂(1:1:0) has been established and their chemical individuality has been confirmed by chemical, X-ray, and DT-analyses. Proceeding from data on the structure of Cd(C₆H₅COO)₂ · 2 H₂O and the composition of the 1:1:0 double salts as well as using Pauling's rules for the most probable spacial disposition of the ions, the crystal structure type of the double salts obtained are predicted.     

The crystal and molecular structure of three homologue 1,4-dialkanoyloxy-biphenyls (SYM-n)

The three homologue compounds with the general formula C_nH_2n+1 COO C₆H₄ C₆H₄ OOC C_nH_2n+1 (SYM-n) crystallize in the following space groups: SYM-1: triclinic, P1 , a = 7.400(6), b = 9.227(3), c = 10.579(3) Å, α = 85.97(3), β = 89.09(3), γ = 71.47(3)°; SYM-2; monoclinic, P2₁/c, a = 11.712(7), b = 5.648(1), c = 12.408(6), Å, β = 103.84(3)°; SYM-5: triclinic, P1, a = 5.505(4), b = 8.342(8), c = 24.79(2) Å, α = 86.67(3), β = 85.45(6), γ = 71.74(7)°. The structures have been solved by direct methods and refined to R = 0.075, 0.061 and 0.053, respectively. The packing arrangements show a layer-like structure. The layers are almost separated for SYM-1 as well as for SYM-2 and interdigitated for the structure of SYM-5.     

Catena-Poly[[[2,4-dichloro-6-{[(2-hydroxyethyl)imino]methyl}phenolato-κ3N,O,O']-copper(II)]-μ-chlorido]monohydrate]: Synthesis,structural, spectroscopic and luminescent properties

A new chloride bridged polymeric Cu(II) complex, [Cu(HL)(μ-Cl).H₂O]_n, 1, (H₂L = 2,4-dichloro-6-{[(2-hydroxyethyl)imino]methyl}phenol) has been synthesized and characterized by elemental-spectral analysis, crystal structure analysis and photoluminescence measurements. The Copper(II) atom is five-coordinate in a slightly distorted square-pyramidal geometry (τ = 0.085), with one N and two O atoms of the Schiff base ligand and one Cl atom defining the basal plane and a symmetry-related Cl atom occupying the apical position. The bridging Cl atom lies in apical position for one Cu(II) ion and basal for the other, and it makes this structural arrangement unusual. The linked moieties form polymeric zigzag chains running along the c axis. This zigzag chains connect each other with intramolecular and intermolecular O–H···O hydrogen bonds, which form 3D structure through π?π interactions. Furthermore, the photoluminescence properties of H₂L and 1 were investigated, they exhibit unique bright green visible emissions in the solid state, under the excitation of 349 nm UV light. The strong luminescence emission of them makes 1 a potentially useful photoactive material in photo-physical chemistry.     

The Crystal and Molecular Structure of Mesomorphic 1,4-Dipentadecanoyloxy-biphenyl (SYM-14)

The compound with the general formula C_nH_2n+1 –COO–C₆H₄–C₆H₄–OOC–C_nH_2n+1, n = 14 (SYM- 14) crystallizes in the triclinic space group P 1 , with a = 5.431(5), b = 9.346(8), c = 39.172(51) Å, α = 92.60(15), β = 90.65(15), γ = 100.364(8)°. The crystal structure was solved by direct methods. Least-squares refinement leads to a final R value of 0.092 for 1575 observed reflections, with I > 2σs(I). The packing arrangement follows the same building principles found recently for the first three members of the well known homologous series of liquid crystalline terephthalylidine-anilines (TBAA-n).     

A Novel Coordination Structure of Dichromates Bonding to Copper (II): [Cu(bipy)2(Cr2O7)] · 2 H2O

Dark-green multimetal compound crystal [Cu(bipy)₂(Cr₂O₇)]· 2 H₂O was obtained from aqueous solution of Cu(NO₃)₂, K₂Cr₂O₇ and bipyridine. The crystal structure was determined by X-ray crystallography: triclinic P1 , a = 7.716(3) Å, b = 9.656(3) Å, c = 15.517(5)Å, α = 77.41(3)°, β = 81.04(3)°, γ = 82.33(3)°, Z = 2. In this compound, two chromium atoms and a copper atom are linked by two oxo bridges (Cu(II) O Cr(VI) O Cr(VI)). The copper coordination polyhedron corresponds to a five-coordinated distorted trigonal bipyramid.     

Structure and self-assembly synthesis of a novel heterometallic one-dimensional coordination polymer: {[Cu(II)(DETA)I·DMF]2[Pb2I6]} n

A novel organic–inorganic hybrid coordination polymer {[Cu(II)(DETA)I·DMF]₂[Pb₂I₆]} _n (DETA = diethylene triamine, DMF = N,N′-dimethyl formamide) was synthesized by the reaction of CuSO₄·6H₂O, DETA, Pb(NO₃)₂ and NaI in DMF/H₂O mixed solvent at room temperature. Structural characterization of X-ray single diffraction reveals that the polymeric negative chain [Pb₂I₆] _n ²⁻ is built up by face-sharing of PbI₆ octahedrons. Upon the hydrogen bonds interaction between N–H···I and N–H···O, structure-directing reagent chain {[Cu(II)(DETA)I·DMF]₂} _n ²⁺ presents one-dimension arrangement. Structure-directing reagent chains and polymeric negative chains are in combination with each other by static attracting force to form the so-called hybrid structure. The title compound was further characterized by IR, EA, UV-Vis and fluorescence spectrum.     

Synthesis,characterization and photoluminescence studies of new Cu(II) complex

In the current work, a new coordination complex, [Cu(HL)₂], 1 [H₂L = 2–((E)–(2–hydroxypropylimino)methyl)–4–nitrophenol] was successfully synthesized and characterized by IR, UV-vis and photoluminescence spectroscopic techniques, single crystal and powder X-ray diffraction measurements. In the crystalline structure of complex 1, the aliphatic –OH group of the ligand is not coordinated and points away from the metal coordination zone, and also actively participates in intermolecular bifurcated O?H···O hydrogen bonds which link the molecules to form hydrogen-bonded linear chains. C?H···π and π···π contacts also connect the molecules in the structure which form to 3D structure. This hydrogen bonded polymeric networks lie in the bc-plane and stacks along to the a-axis. Furthermore, complex 1 and its ligand H₂L display an intense navy-blue emission and blue emission in the solid state at room temperature, respectively, when they are excited under UV light.     

A new one-dimensional oxalato- and acetato-bridged Mn(II) polymer with 1,10-phenanthroline as terminal ligand: [Mn2(C12N2H8)2(μ-C2O4)(μ-CH3COO)2] n ·4nH2O

A new oxalato- and acetato-bridged Mn(II) polymer, [Mn₂(C₁₂N₂H₈)₂(μ-C₂O₄)(μ-CH₃COO)₂] _n ·4nH₂O was synthesized and characterized by X-ray diffraction analysis. The compound exhibits a one-dimensional chain-like structure, in which the Mn atom is coordinated by two nitrogen atoms and four carboxyl oxygen atoms with octahedral coordination geometry. As far as we are aware, this type of coordination polymer involving the simultaneously bridging oxalate and acetate ligands has not been studied so far.     

Synthesis, Crystal Structure of a New Co(II) Complex with Pyrazine-2,3,5,6-tetracarboxylic Acid

Abstract A new complex [Co(H₂pztc)(bpy)H₂O] (H₄pztc = pyrazine-2,3,5,6-tetracarboxylic acid, bpy = 2,2′-bipyridine) has been synthesized by hydrothermal reactions of Co(NO₃)₂ · 6H₂O with H₄pztc and bpy and characterized by IR and X-ray diffraction single crystal structure analysis. It belongs to monoclinic system, P2₁/c space group with a = 13.454(2) ?, b = 12.939(2) ?, c = 11.4993(19) ?, α = 90°, β = 111.640(3)°, γ = 90°. This complex is assembled into 3D supramolecular architecture by hydrogen bonds (O–H···O, C–H···O). Index Abstract A new complex of cobalt(II) with pyrazine-2,3,5,6-tetracarboxylic acid and 2,2′-bipyridine is assembled by intermolecular hydrogen bonds forming 2D layer and 3D supramolecular network.      

A Novel Three Dimensional Organic–Inorganic Hybrid Based Porous Phase: Synthesis and Characterization of Reduced Oxovanadium pyromellitate, [VIV2O2(H2O)2(C6H2(COO)4)]

The hydrothermal reaction of a mixture of VOSO₄ · xH₂O, 1,2,4,5-benzenetetracarboxylic acid (pyromellitic acid) and 0.1 M H₂SO₄ for 72 h at 160 °C gives blue needle like crystals of [V^IV ₂O₂(H₂O)₂(C₆H₂(COO)₄)] in 30% yield. The compound has a porous 3-D extended network structure having a rigid architecture which is held together by the multidentate functionalities of 1,2,4,5-benzenetetracarboxylate ligand. Crystal data for the compound: monoclinic space group C 2/c (No:15), a = 11.756(5) ?, b = 9.645(3) ?, c = 11.822(7) ?, β = 107.10(4)°, Z = 8. The compound constitutes the first example of a fully reduced oxovanadium based solid incorporating the organic ligand. This article consists of synthesis, crystal structure and characterization of [V^IV ₂O₂(H₂O)₂(C₆H₂(COO)₄)].