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Hydrothermal Reaction (hydrothermal + reaction)
Selected AbstractsFormation of Novel ZSM-5/Porous Mullite Composite from Sintered Kaolin Honeycomb by Hydrothermal ReactionJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 5 2000Hiroaki Katsuki The formation and properties of continuous ZSM-5 film on a porous mullite honeycomb have been investigated. The porous mullite honeycomb coated with ZSM-5 film provides a novel microporous (0.5 nm in diameter),macroporous (0.5,0.6 ,m in diameter) composite. Amorphous silica-glass in the kaolin honeycomb sintered at 1650°C is used as a source for ZSM-5 formation. The honeycomb is hydrothermally treated in NaOH, tetrapropylammonium bromide, and water to prepare a novel honeycomb,zeolite composite by in situ crystallization of ZSM-5 film. This paper describes the effects of hydrothermal conditions,such as reaction temperature, time, and concentration of NaOH solution,on the formation of ZSM-5 film on the honeycomb, and on the mechanical strength and porous properties of the honeycomb composite. [source] Crystal Structure, Thermal Stability and Luminescence of Coordination Polymer [Cd(BBP)(p -PDOA)]nCHINESE JOURNAL OF CHEMISTRY, Issue 8 2007Yan Yang Abstract Hydrothermal reaction of Cd(NO3)2·4H2O with bbp and p -PDOAH2 at 140 °C yielded a novel 1D cadmium(II) coordination polymer, [Cd(bbp)(p -PDOA)]n (bbp2,6-bis(benzimidazol-2-yl)pyridine, p -PDOAp -phenylenedioxy- diacetate dianion), in which CdN3O4 pentagonal bipyramids were linked by p -PDOA ligands in a bis-bidentate mode to construct a zigzag chain with the adjacent Cd···Cd distance of 1.14(1) nm. There exists a 2D supramolecular network linked by ,-, stacking with a face-to-face distance of 0.35(1) nm between the 2,6-bis(benzimidazol-2-yl) pyridine ligands and hydrogen-bonding interactions (0.27(4) nm). A 3D supramolecular network was further constructed by these non-covalent interactions between the zippers. The TG/DTG showed that its chain skeleton was thermally stable up to 389 °C and the blue fluorescent emission of the complex was determined at 428 nm in a solid state with its long decay lifetime of 7.24 ns. [source] Syntheses, Crystal Structures, and Characterizations of a Series of New Layered Lanthanide Carboxylate-PhosphonatesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 10 2006Si-Fu Tang Abstract Hydrothermal reactions of different lanthanide(III) salts with (H2O3PCH2)2NCH2COOH (H5L1) led to two new layeredlanthanide(III) carboxylate-diphosphonates, namely La(H2L1)(H2O)2·H2O (1) and La(H2L1)(H2O) (2). The structure of compound 1 features a layered architecture in which the nine-coordinate La3+ ions are bridged by phosphonate groups of the ligands. The carboxylate group of the phosphonate ligand remains protonated and is involved in the interlayer hydrogen bonding. Compound 2 features a double layer structure in which the La3+ ion is eight-coordinated and the carboxylate group of the ligand is chelated to a La3+ ion in a bidentate fashion. Hydrothermal reactions of lanthanide(III) salts with 4-HOOC,C6H4,CH2N(CH2PO3H2)2 (H5L2) afforded three new compounds, namely, La(H4L2)(H3L2)(H2O)·2H2O (3), Er(H3L2)(H4L2) (4), and Er(HL3)(H2L3)(H2O) (5) [H2L3 = H2O3PCH2N(CHO)(CH2,C6H4,COOH)]. H2L3 was formed by the in situ oxidation of one P,C bond of the H5L2 ligand. Compound 3 features a (002) lanthanum(III) phosphonate layer in which the seven-coordinate La3+ ions are bridged by diphosphonate moieties of the ligands. The carboxylate group remains protonated and is involved in the interlayer hydrogen bonding. The structure of compound 4 contains a 1D chain along the a axis in which each pair of ErO6 octahedra is bridged by a pair of phosphonate groups. These 1D chains are further interconnected by hydrogen bonds between noncoordinated phosphonate oxygen atoms into a (002) layer with the phenyl carboxylate groups hanging on the interlayer space. The structure of compound 5 is also layered. The interconnection of Er3+ ions by bidentate and tetradentate bridging phosphonate groups resulted in a (002) inorganic layer with the organic groups orientated to the interlayer space. Luminescence properties of compounds 4 and 5 have also been studied.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Hydrothermal synthesis of nano-crystalline BaMoO4 under mild conditions using simple additiveCRYSTAL RESEARCH AND TECHNOLOGY, Issue 2 2010Guangru Tian Abstract Large-scale high-quality BaMoO4 nanocrystals have been synthesized in aqueous solutions under mild conditions with citrate as a simple additive. The crystals have bone-like, spindle-like and wheatear-like morphologies assembled from nanoparticles, nanofibers and have been characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) techniques. The results showed that experimental parameters had great influences on the shape evolution of products. The adjustment of these parameters such as room temperature stirring time, reaction temperature and reaction time of hydrothermal reaction, can lead to obvious morphology changes of products, and the growth mechanism has been proposed. Room-temperature photoluminescence indicated that the as-prepared BaMoO4 nanocrystals had a strong blue emission peak at 481.5 nm. This facile route could be employed to synthesize more promising nanomaterials with interesting self-assembly structures. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Hydrothermal Synthesis and Structural Characterization of the High-Valent Ruthenium-Containing Polyoxoanion [{PW11O39}2{(HO)RuIV,O,RuIV(OH)}]10,EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 13 2008Su-Wen Chen Abstract The high-valent ruthenium-containing [{PW11O39}2{(HO)RuIV,O,RuIV(OH)}]10, anion (1) has been synthesized by hydrothermal reaction and characterized by X-ray diffraction, IR, multinuclear (31P and 183W) NMR spectroscopy andelectrochemistry. Single-crystal analysis was carried outon Rb10[{PW11O39}2{(HO)RuIV,O,RuIV(OH)}]·21H2O, which crystallizes in the monoclinic system, space group P21/n, with a = 11.1912(14), b = 21.9257(12), c = 38.7310(96) Å, , = 94.682(19)°, V = 9472(3) Å3, Z = 4. Polyanion 1 consists of two lacunary [,-PW11O39]7, anions connected by a linear {(HO)Ru,O,Ru(OH)}4+ unit. Each ruthenium ion achieves six-coordination through interaction with two terminal oxo ligands from the lacuna of each [PW11O39]7, anion.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Synthesis, Crystal Structure and Characterisation of a Novel Chiral Mixed-Valence Vanadium Oxide Hybrid, [V5O11(dien)3]EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 15 2005Ming-Lai Fu Abstract The novel chiral mixed-valence vanadium oxide hybrid [V5O11(dien)3] (1) (dien = NH2C2H4NHC2H4NH2) has been synthesised by a hydrothermal reaction of V2O5 and dien in aqueous solution and characterised by elemental analysis, IR spectroscopy, TG-DSC analysis, magnetism, EPR spectroscopy, single-crystal X-ray diffraction and powder XRD. The X-ray diffraction analysis revealed that the structure of 1 can be regarded as being constructed from two [VVO4]3, groups bicapping three [VIVO(dien)]2+ units to form a discrete asymmetric pentanuclear vanadium complex with the dien ligands coordinating directly to the vanadium(IV) centres. Compound 1 exhibits an interesting tube-like 3D supramolecular structure due to abundant hydrogen-bonding interactions between the oxygen atoms of the inorganic backbone and the hydrogen atoms of the dien ligands from adjacent molecules. The variable-temperature magnetic susceptibility data of 1 suggest a weak ferromagnetic interaction among V4+ ions in the cluster. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Three-Dimensional Lanthanoid-Containing Coordination Frameworks: Structure, Magnetic and Fluorescent PropertiesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 4 2005Hong-Tao Zhang Abstract Two lanthanoid-containing 3D coordination polymers, [Gd2L3(H2O)2]n (1) and {[TbL1.5(H2O)]·0.5H2O}n (2) (L = succinate), have been prepared by hydrothermal reaction. The difference in structure between the two 3D coordination polymers is a result of the flexibility of the ligand conformation. The magnetic properties of 1 and 2 have been investigated in the 1.8,300 K range. Both complexes exhibit ferromagnetic interaction between lanthanoid ions. AC magnetic measurements revealed long-range magnetic order in complex 2. Especially 2 integrates the ferromagnetic, fluorescent and porous properties into a single entity. This motif may be developed to achieve new multifunctional molecular-based materials. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Synthesis, Crystal Structure, and Magnetic Properties of Mn2(OH)2SO4: A Novel Layered HydroxideEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 11 2004Mohsen Ben Salah Abstract Mn2(OH)2SO4, obtained as pink prismatic crystals by the hydrothermal reaction of MnSO4·H2O and NaOH at 240 °C for 24 h, consists of layers of Mn hydroxide connected to each other through µ6 -sulfate ions. Each layer exhibits vacancies, and each vacant space is capped at the top and bottom by the sulfate groups. The compound is paramagnetic above 50 K (C = 4.36 emu K mol,1, µeff = 5.91 µB, , = ,100 K). Below 45 K, the magnetization increases slightly, indicating canted-antiferromagnetic (TNéel = 42±1 K) behavior consistent with the linear dependence of the magnetization as a function of the field at 2 K, which reaches only 0.4 µB at 50 kOe, and the lack of any imaginary component of the ac-susceptibilities (ac = alternating current). (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Site-Selective Deposition of Metal Nanoparticles on Aligned WO3 Nanotrees for Super-Hydrophilic Thin FilmsADVANCED MATERIALS, Issue 13 2009Masachika Shibuya Highly aligned WO3 nanotrees are grown on metal tungsten by a simple hydrothermal reaction. Pd nanoparticles are selectively deposited on the WO3 nanotrees by a photocatalytic reduction reaction. Photocatalytic oxidation activity depends strongly on the position of the deposited Pd nanoparticles, and the WO3 nanotrees with Pd nanoparticles deposited at the bottom position exhibited efficient super-hydrophilicity. [source] Cylindrical Silver Nanowires: Preparation, Structure, and Optical Properties,ADVANCED MATERIALS, Issue 21 2005M. Sun Cylindrical and pentagonal Ag nanowires (see Figure) are selectively prepared in amorphous carbonaceous sheaths via a controlled hydrothermal reaction. Results indicate that the amorphous coating layer is responsible for the cross-section symmetry selected synthesis. The distinctive optical properties measured fit well with the theoretical predictions, and applications in electronic nanodevices are envisaged. [source] Synthesis and Photocatalytic Activity of Highly Ordered TiO2 and SrTiO3/TiO2 Nanotube Arrays on Ti SubstratesJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 9 2010Xuming Zhang Highly ordered TiO2 nanotube arrays (TiO2 -NTAs) are produced by electrochemical anodization of a Ti foil in ammonium fluoride (NH4F),ethylene glycol solution. Photocatalytic (PC) investigations indicate that the length of the NTAs plays an important role in their photoactivity. The PC activity increases initially with the NT length and then decreases and the optimum length that yields the highest PC is 6.2 ,m for TiO2 -NTAs. The TiO2 -NTAs are further converted to heterojunction strontium titanate (SrTiO3)/TiO2 -NTAs by a hydrothermal reaction in Sr(OH)2 solution. As the hydrothermal reaction proceeds, more TiO2 is converted into SrTiO3 and the thickness of the SrTiO3 layer increases. The SrTiO3/TiO2 -NTAs exhibit variable PC activities that depend on the hydrothermal reaction time, and the SrTiO3/TiO2 -NTAs hydrothermally treated for 1 h or less have enhanced PC properties. The advantage of combining TiO2 and SrTiO3 stems from the difference in the flatband potential, thereby improving the separation of the photogenerated electron,hole pairs and consequently the PC activity. [source] A novel two-dimensional framework based on unprecedented cadmium(II) chainsACTA CRYSTALLOGRAPHICA SECTION C, Issue 2 2009Jie Qin The bent ligand 4-[(1H -1,2,4-triazol-1-yl)methyl]benzoic acid (HL) has been used to create the novel two-dimensional coordination polymer poly[,2 -aqua-,2 -chlorido-{,2 -4-[(1H -1,2,4-triazol-1-yl)methyl]benzoato}cadmium(II)], [Cd(C10H8N3O2)Cl(H2O)]n, under hydrothermal reaction of HL with cadmium chloride. The crystallographically unique Cd atom is seven-coordinated in an approximately pentagonal,bipyramidal environment of two carboxylate O atoms, two water O atoms, two Cl atoms and one triazole N atom. A notable feature is the presence of zigzag ...Cd...Cd... inorganic chains, in which neighboring CdII ions are doubly bridged by pairs of ,2 -Cl atoms and ,2 -H2O ligands in an alternating fashion. To the authors' knowledge, this is the first example containing this bridging mode in a cadmium(II) framework. The chains are connected to one another through the bridging L, ligand into a two-dimensional undulating network. All of the two-dimensional nets stack exactly together in an ,AA, stacking sequence along the crystallographic b axis. Neighboring layers are further linked into a three-dimensional framework via interlayer hydrogen-bonding interactions. [source] Coordination Chemistry of Conformation-Flexible 1,2,3,4,5,6-Cyclohexanehexacarboxylate: Trapping Various Conformations in Metal,Organic FrameworksCHEMISTRY - A EUROPEAN JOURNAL, Issue 24 2008Jing Wang Abstract To study the conformations of 1,2,3,4,5,6-cyclohexanehexacarboxylic acid (H6L), eleven new coordination polymers have been isolated from hydrothermal reactions of different metal salts with 1e,2a,3e,4a,5e,6a -cyclohexanehexacarboxylic acid (3e+3a, H6LI) and characterized. They are [Cd12(,6 - LII)(,10 - LII)3(,-H2O)6(H2O)6],16.5,H2O (1), Na12[Cd6(,6 - LII)(,6 - LIII)3],27,H2O (2), [Cd3(,13 - LII)(,-H2O)] (3), [Cd3(,6 - LIII)(2,2,-bpy)3(H2O)3],2,H2O (4), [Cd4(,4 - LVI)2(4,4,-Hbpy)4(4,4,-bpy)2(H2O)4],9.5,H2O (5), [Cd2(,6 - LII)(4,4,-Hbpy)2(H2O)10],5,H2O (6), [Cd3(,11 - LVI)(H2O)3] (7), [M3(,9 - LII)(H2O)6] (M=Mn (8), Fe (9), and Ni (10)), and [Ni4(OH)2(,10 - LII)(4,4,-bpy)(H2O)4],6,H2O (11). Three new conformations of 1,2,3,4,5,6-cyclohexanehexacarboxylate, 6e (LII), 4e+2a (LIII) and 5e+1a (LVI), have been derived from the conformational conversions of LI and trapped in these complexes by controlling the conditions of the hydrothermal systems. Complexes 1 and 2 have three-dimensional (3D) coordination frameworks with nanoscale cages and are obtained at relatively low temperatures. A quarter of the LI ligands undergo a conformational transformation into LII while the others are transformed into LIII in the presence of NaOH in 2, while all of the LI are transformed into LII in the absence of NaOH in 1. Complex 3 has a 3D condensed coordination framework, which was obtained under similar reaction conditions as 1, but at a higher temperature. The addition of 2,2,-bipyridine (2,2,-bpy) or 4,4,-bipyridine (4,4,-bpy) to the hydrothermal system as an auxiliary ligand also induces the conformational transformation of H6LI. A new LVI conformation has been trapped in complexes 4,7 under different conditions. Complex 4 has a 3D microporous supramolecular network constructed from a 2D LIII -bridged coordination layer structure by ,-, interactions between the chelating 2,2,-bpy ligands. Complexes 5,7 have different frameworks with LII/LVI conformations, which were prepared by using different amounts of 4,4,-bpy under similar synthetic conditions. Both 5 and 7 are 3D coordination frameworks involving the LVI ligands, while 6 has a 3D microporous supramolecular network constructed from a 2D LII -bridged coordination layer structure by interlayer N4,4,-HbpyH,,,O(LII) hydrogen bonds. 3D coordination frameworks 8,11 have been obtained from the H6LI ligand and the paramagnetic metal ions MnII, FeII, and NiII, and their magnetic properties have been studied. Of particular interest to us is that two copper coordination polymers of the formulae [{CuII2(,4 - LII)(H2O)4}{CuI2(4,4,-bpy)2}] (12,,) and [CuII(Hbtc)(4,4,-bpy)(H2O)],3,H2O (H3btc=1,3,5-benzenetricarboxylic acid) (12,,) resulted from the same one-pot hydrothermal reaction of Cu(NO3)2, H6LI, 4,4,-bpy, and NaOH. The Hbtc2, ligand in 12,, was formed by the in situ decarboxylation of H6LI. The observed decarboxylation of the H6LI ligand to H3btc may serve as a helpful indicator in studying the conformational transformation mechanism between H6LI and LII,VI. Trapping various conformations in metal-organic structures may be helpful for the stabilization and separation of various conformations of the H6L ligand. [source] Linking Two Distinct Layered Networks of Nanosized {Ln18} and {Cu24} Wheels through Isonicotinate LigandsCHEMISTRY - A EUROPEAN JOURNAL, Issue 1 2008Jian-Wen Cheng Abstract A new series of heterolanthanide(III)-copper(I) wheel-cluster complexes [Ln6(,3 -O)2](IN)18[Cu8(,4 -I)2(,2 -I)3],H3O (IN=isonicotinate; Ln=Y 1, Nd 2, Dy 3, Gd 4, Sm 5, Eu 6, Tb 7) were prepared by hydrothermal reaction at low pH. X-ray crystallographic studies reveal that two unusual trinuclear [Ln3(,3 -O)] and tetranuclear [Cu4(,4 -I)] cores are successfully used as secondary building units to make two different nanosized wheels [Ln18(,3 -O)6(CO2)48]6,, {Ln18}, and [Cu24(,4 -I)6(,2 -I)12]6+, {Cu24}, with 12-rings and a diameter of 26.7 and 26.4,Å, respectively. The wheels are further assembled into two-dimensional (2D) {Ln18} and {Cu24} networks, the linkages between two distinct layered networks of {Ln18} and {Cu24} wheels by IN pillars along the c axis giving a series of unprecedented three-dimensional (3D) sandwich frameworks. To our knowledge, compounds 1,7 are the first examples containing two different layered networks of nanosized Ln and transition metal (TM) wheels in wheel-cluster chemistry. The IR, UV/Vis, thermogravimetric analysis (TGA), luminescent, and magnetic properties of these complexes were also studied. [source] An Unprecedented 2D 4f-3d-5d Multimetal-Isonicotinic Acid Complex: Synthesis, Structural Characterization and Magnetic PropertiesCHINESE JOURNAL OF CHEMISTRY, Issue 9 2008Wen-Tong CHEN Abstract A novel heterometallic metal-isonicotinic acid inorganic-organic hybrid complex [Zn0.5(H2O)]{(Hg2Cl5)- [Er(C6NO2H4)3(H2O)2]}(HgCl2)·0.5CH3OH·0.5H2O (1) has been successfully synthesized via a hydrothermal reaction and structurally characterized by single-crystal X-ray diffraction. Complex 1 crystallizes in the space group C2/c of the monoclinic system with eight formula units in a cell: a=34.165(4) Å, b=9.4692(8) Å, c=24.575(3) Å, , =115.090(5)°, V=7200(1) Å3, C18.50H21Cl7ErHg3N3O10Zn0.50, Mr=1495.25, Dc=2.759 g/cm3, T=293(2) K, µ(Mo K,) =15.954 mm,1, F(000) =5400 and R1/wR2=0.0561/0.0909 for 3157 observed reflections [I>2,(I)] and 6468 unique reflections. Complex 1 is characteristic of a novel 2D {(Hg2Cl5)[Er(C6NO2H4)3(H2O)2]} layered structure constructed from the [Er(C6NO2H4)3(H2O)2] chains interconnected by the Hg2Cl5, linkers. The 2D {(Hg2Cl5)[Er(C6NO2H4)3(H2O)2]} layers, mercury chloride and the lattice water molecules are held together via hydrogen bonds to form a three-dimensional framework with the methanol molecules and the hydrated zinc ions located in the cavities. The magnetic properties show that complex 1 exhibits antiferromagnetic-like interactions. [source] Synthesis and Characterization of 1-, 2-, and 3-Dimensional Bimetallic UO22+/Zn2+ PhosphonoacetatesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 8 2010Karah E. Knope Abstract Four bimetallic UO22+/Zn2+ phosphonoacetates have been prepared from hydrothermal reactions of uranyl nitrate, zinc nitrate, and triethyl phosphonoacetate. These compounds, (UO2)2(PPA)2(H2O)2·Zn(H2O)6·4H2O (1), (UO2)4(PPA)2(HPPA)2·Zn(H2O)6·5H2O·(2), (UO2)2(H2O)2(PPA)2Zn(H2O)4 (3), and (UO2)2(PPA)2(HPPA)Zn2(H2O)2·3(H2O) (4), adopt 1-, 2-, and 3-dimensional architectures wherein the UO22+ cation exhibits coordination preference for the phosphonate over the carboxylate oxygen atoms. The Zn2+ metal centers show an increased degree of ligand coordination with increasing reaction temperature. At 120 °C, compounds 1 and 2 are formed. These structures are 1- and 2-dimensional, respectively, and contain fully hydrated [Zn(H2O)6]2+ cations. At 150 °C and 180 °C, the HPPA ligand displaces H2O molecules from the inner Zn2+ hydration sphere and binds to the metal centers via a ,CO2H oxygen atom in 3 and both carboxylate and phosphonate oxygen atoms in 4. The overall Zn2+ reaction can be expressed by the equation Zn(H2O)62+ + HPPA [rlarr2] Zn(H2O)5(HPPA) + H2O. Presented here are the syntheses, structures, and characterization of these materials. [source] Microwave-Assisted Hydrothermal Synthesis of Structurally and Morphologically Controlled Sodium Niobates by Using Niobic Acid as a PrecursorEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 8 2008Amauri J. Paula Abstract There are many advantages to using a microwave as a source of heat in hydrothermal reactions. Because it is a quick and homogeneous way to crystallize ceramic powders, it was used in this work for the production of antiferroelectric sodium niobate (NaNbO3) in a cubic-like form and its intermediary phase, disodium diniobate hydrate (Na2Nb2O6.H2O), with a fiber morphology. The syntheses were carried out by treating niobic acid (Nb2O5·nH2O) with NaOH. By changing the reaction time and the concentration of the reactants, particles with different structures and different morphologies could be obtained. The structural evolution of the products of this reaction was elucidated on the basis of the arrangement of the NbO6 octahedral units. Conclusive results were obtained with morphological and structural characterizations through XRD, TEM, MEV, and NMR and Raman spectroscopy. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Novel (3,4)- and (4,5)-Connected Lanthanide Metal,Organic FrameworksEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 1 2008Xian-Wen Wang Abstract The three-dimensional lanthanide noninterpenetrating metal,organic frameworks formulated as [Ln(3,5-pdc)(C2O4)0.5(H2O)2]·H2O (Ln = LuIII, GdIII, TmIII and YbIII for complex 1,4, respectively; 3,5-pdc = 3,5-pyridinedicarboxylate) were synthesized by hydrothermal reactions of 3,5-H2pdc with lanthanide oxide and perchloric acid. Compound 1 shows (3,4)-connected (4.82)(4.85) dmc-type topological network, and complexes 2,4 display the novel (4,5)-connected (44.6.8)(44.62.84) xww-type topology. The lanthanide-mediated transformation of CO2 to oxalate under hydrothermal conditions was observed. The fluorescence properties of complexes 1,4 were investigated. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Synthesis, Crystal Structures, and Photophysical Properties of Two Novel Lead(II),SIP Coordination Polymers (NaH2SIP = 5-Sulfoisophthalic Acid Monosodium Salt) Containing Tetranuclear Lead(II) UnitsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 8 2006Qing-Yan Liu Abstract Two new PbII,SIP coordination polymers, {[Pb4(OH)2(SIP)2(H2O)](H2O)5}n (1) and [Pb3(SIP)2(H2O)5]n (2), have been synthesized by hydrothermal reactions of Pb(OH)2 or Pb(NO3)2 and 5-sulfoisophthalic acid monosodium salt (NaH2SIP) at 160 °C, respectively. Single-crystal X-ray diffraction reveals that compound 1 has a 2D brick-wall-like architecture constructed from 1D tapes containing the basketlike tetranuclear [Pb4(,3 -OH)2(COO)2]. Compound 2 has a 2D-layered structure, which is constructed from a 1D-ladder structure composed of the cyclic [Pb4(SIP)2(COO)2] grid with the four Pb atoms nearly coplanar. In the solid state, compound 1 exhibits blue photoluminescence with the maximum emission intensity at 436 nm upon excitation at 335 nm. Compound 2 shows phosphorescence with the maximum emission intensity at 603 nm upon excitation at 426 nm. Both compounds have also been characterized by elemental analysis, IR spectra, TG analysis, and powder X-ray diffraction. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Syntheses and Crystal Structures of Two Novel Zinc(II) Coordination PolymersEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 14 2003Jun Tao Abstract Two novel zinc(II) coordination polymers, [Zn3(,3 -OH)2(nip)2] (1) and [Zn2(nip)2(4,4,-bpy)3·(OH2)] (2) (H2nip = 5-nitroisophthalic acid, 4,4,-bpy = 4,4,-bipyridyl), were obtained by the hydrothermal reactions of zinc nitrate, 5-nitroisophthalate (nip) (for 1) and zinc nitrate, 5-nitroisophthalate and 4,4,-bipyridyl (for 2). Complex 1 displays a two-dimensional structure that is built from [Zn3(,3 -OH)2]n chains, while complex 2 is a three-dimensional structure formed by the interpenetration of two-dimensional hydrogen-bonded bilayers. The photoluminescent properties of complex 1 have also been investigated. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source] Hochdurchsatz-Methoden in der Festkörperchemie.CHEMIE IN UNSERER ZEIT (CHIUZ), Issue 5 2007Schneller zum Ziel Abstract Hochdurchsatz-Methoden zeichnen sich gegenüber konventionellen Methoden durch eine größere Effizienz aus. Mittlerweile steht im Bereich der Anorganischen Festkörperchemie und der Materialwissenschaften eine Vielzahl von Werkzeugen zur Verfügung, um die Entdeckung und Optimierung von Materialien durch Verwendung von HD-Methoden schneller voranzutreiben. Für alle Arbeitstechniken gilt: Das Ausmaß der Automatisierung, Parallelisierung und Miniaturisierung sowie die Integration aller Einzelschritte in einen Gesamtprozess bestimmt die Effizienz einer HD-Methodik. Durch eine systematische Untersuchung des Parameterraumes und durch sorgfältige Datenevaluierung (möglichst Software-gestützt) können Trends gefunden werden, die zu einem besseren Verständnis der untersuchten Systeme beitragen. Der vorgestellte Ansatz zur HD-Untersuchung von Solvothermalreaktionen erlaubt die automatisierte Synthese und Charakterisierung von bis zu 48 Produkten ohne die Proben einzeln manipulieren zu müssen. Der geringe Reagenzienverbrauch zusammen mit der Möglichkeit, die Reaktionen unter identischen Prozessparametern (Temperatur, Zeit, Druck, usw.) durchführen zu können, ermöglichen die systematische Untersuchung eines größeren Parameterraumes. An Hand zahlreicher Beispiele haben wir das Potential von Hochdurchsatz- Methoden bei der Entdeckung neuer Verbindungen, der Optimierung von Reaktionen, beim Auffinden von Reaktionstrends sowie der Untersuchung des Einflusses von Prozessparametern gezeigt. High-throughput (HT) methods applied to materials discovery have attracted much attention over the last few years because they permit a fast and efficient investigation of parameter space while consuming only small amounts of starting materials. Nowadays, many different HT techniques in solid state science are employed in order to accelerate the discovery and optimization of materials. The degree of parallelisation, automation, and miniaturization determines the efficiency of a HT methodology. Systematic investigation of parameter space and careful data analysis allow the identification of reaction trends and may give important guidance in better understanding of reaction systems. The described HT methodology for solvothermal reactions allows the systematic investigation of 48 different hydrothermal reactions at a time. The methodology includes automatic dispensing of solids and liquids, followed by homogenization, pH measurement, synthesis, isolation, washing as well as automated phase analysis by X-ray diffraction without the manipulation of individual samples. The focus of this article is on the application of HT methods in the investigation of the parameter space in solid state sciences. Based on selected examples, the power of HT methods in the discovery of new compounds, the optimization of reactions, the identification of reaction trends, as well as the investigation of the influence of process parameters is described. The large amount of data obtained in a short time leads to an improvement towards the understanding of the role that synthesis and process parameters play in the formation of compounds and materials. [source] Coordination Chemistry of Conformation-Flexible 1,2,3,4,5,6-Cyclohexanehexacarboxylate: Trapping Various Conformations in Metal,Organic FrameworksCHEMISTRY - A EUROPEAN JOURNAL, Issue 24 2008Jing Wang Abstract To study the conformations of 1,2,3,4,5,6-cyclohexanehexacarboxylic acid (H6L), eleven new coordination polymers have been isolated from hydrothermal reactions of different metal salts with 1e,2a,3e,4a,5e,6a -cyclohexanehexacarboxylic acid (3e+3a, H6LI) and characterized. They are [Cd12(,6 - LII)(,10 - LII)3(,-H2O)6(H2O)6],16.5,H2O (1), Na12[Cd6(,6 - LII)(,6 - LIII)3],27,H2O (2), [Cd3(,13 - LII)(,-H2O)] (3), [Cd3(,6 - LIII)(2,2,-bpy)3(H2O)3],2,H2O (4), [Cd4(,4 - LVI)2(4,4,-Hbpy)4(4,4,-bpy)2(H2O)4],9.5,H2O (5), [Cd2(,6 - LII)(4,4,-Hbpy)2(H2O)10],5,H2O (6), [Cd3(,11 - LVI)(H2O)3] (7), [M3(,9 - LII)(H2O)6] (M=Mn (8), Fe (9), and Ni (10)), and [Ni4(OH)2(,10 - LII)(4,4,-bpy)(H2O)4],6,H2O (11). Three new conformations of 1,2,3,4,5,6-cyclohexanehexacarboxylate, 6e (LII), 4e+2a (LIII) and 5e+1a (LVI), have been derived from the conformational conversions of LI and trapped in these complexes by controlling the conditions of the hydrothermal systems. Complexes 1 and 2 have three-dimensional (3D) coordination frameworks with nanoscale cages and are obtained at relatively low temperatures. A quarter of the LI ligands undergo a conformational transformation into LII while the others are transformed into LIII in the presence of NaOH in 2, while all of the LI are transformed into LII in the absence of NaOH in 1. Complex 3 has a 3D condensed coordination framework, which was obtained under similar reaction conditions as 1, but at a higher temperature. The addition of 2,2,-bipyridine (2,2,-bpy) or 4,4,-bipyridine (4,4,-bpy) to the hydrothermal system as an auxiliary ligand also induces the conformational transformation of H6LI. A new LVI conformation has been trapped in complexes 4,7 under different conditions. Complex 4 has a 3D microporous supramolecular network constructed from a 2D LIII -bridged coordination layer structure by ,-, interactions between the chelating 2,2,-bpy ligands. Complexes 5,7 have different frameworks with LII/LVI conformations, which were prepared by using different amounts of 4,4,-bpy under similar synthetic conditions. Both 5 and 7 are 3D coordination frameworks involving the LVI ligands, while 6 has a 3D microporous supramolecular network constructed from a 2D LII -bridged coordination layer structure by interlayer N4,4,-HbpyH,,,O(LII) hydrogen bonds. 3D coordination frameworks 8,11 have been obtained from the H6LI ligand and the paramagnetic metal ions MnII, FeII, and NiII, and their magnetic properties have been studied. Of particular interest to us is that two copper coordination polymers of the formulae [{CuII2(,4 - LII)(H2O)4}{CuI2(4,4,-bpy)2}] (12,,) and [CuII(Hbtc)(4,4,-bpy)(H2O)],3,H2O (H3btc=1,3,5-benzenetricarboxylic acid) (12,,) resulted from the same one-pot hydrothermal reaction of Cu(NO3)2, H6LI, 4,4,-bpy, and NaOH. The Hbtc2, ligand in 12,, was formed by the in situ decarboxylation of H6LI. The observed decarboxylation of the H6LI ligand to H3btc may serve as a helpful indicator in studying the conformational transformation mechanism between H6LI and LII,VI. Trapping various conformations in metal-organic structures may be helpful for the stabilization and separation of various conformations of the H6L ligand. [source] Hydrothermal Syntheses, Crystal Structure and Thermal Behavior of [(CH3)2NH2]2[B5O6(OH)4]2·[HCON(CH3)2] and [NH3CH2CH2NH3]2[B14O20(OH)6]CHINESE JOURNAL OF CHEMISTRY, Issue 11 2009Ping Li Abstract Two novel organic base templated nonmetal borates [(CH3)2NH2]2[B5O6(OH)4]2·[HCON(CH3)2] (?) and [NH3CH2CH2NH3]2[B14O20(OH)6] (II) have been synthesized under hydrothermal conditions, and characterized by elemental analyses, FT-IR spectroscopy, X-ray diffraction, and TG-DTA. Their crystal structures were determined from single crystal X-ray diffraction. The crystal structure of compound I is characterized by forming a 3D supramolecular structure with large channels along axes b and c through OH···O hydrogen-bonding among the [B5O6(OH)4], anions. The crystal structure of compound II is characterized by forming a 3D supramolecular structure with large channels along axis a and direction [111] through OH···O hydrogen-bonding among the [B14O20(OH)6]4, anions. The templating organic amine cations in I and II are both obtained through in situ hydrothermal reactions, and are both located in the channels of the 3D supramolecular structure, respectively. Their thermal behavior has been also investigated. [source] Hydrothermal Synthesis, Crystal Structures and Photoluminescence of Two Novel Metal-organic Supramolecular Frameworks Based on Mixed Ligands of Dipyrazino[2,3- f:2,,3,-h]quinoxaline and Pyridine-2,5-dicarboxylic AcidCHINESE JOURNAL OF CHEMISTRY, Issue 9 2008Xiu-Li WANG Abstract Two novel metal-organic frameworks [Zn2(Dpq)2(2,5-pda)2(H2O)2]·2H2O (1) (dipyrazino[2,3- f:2,3,- h]quinoxaline=Dpq) and [Cd2(Dpq)2(2,5-pda)2]·2H2O (2) (pyridine-2,5-dicarboxylic acid=2,5-H2pda) have been obtained from hydrothermal reactions of two different metal(II) nitrates with the same mixed ligands Dpq and 2,5-H2pda, and structurally characterized by elemental analyses, TG, IR spectroscopy, and single-crystal X-ray diffraction analyse. Single-crystal X-ray analyses show that the metal ions are bridged by different coordination modes of 2,5-pda to form a dimer in 1, 2D rhombic grid in 2, respectively. In the compound 1, adjacent dimers are packed through hydrogen bonds and - aromatic stacking interactions to form a distorted , -Po supramolecular structure. In the compound 2, adjacent polymer layers are further linked by hydrogen bonds to form a distorted , -Po 3D supramolecular framework stabilized by - stacking interactions. The different structures of compounds 1 and 2 illustrate the influence of the metal ions and ligands on the self-assembly of polymeric coordination architectures. In addition, the title compounds exhibit blue emission in the solid state at room temperature. [source] | |||||||||||||