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X-ray Powder Diffraction (x-ray + powder_diffraction)
Kinds of X-ray Powder Diffraction Terms modified by X-ray Powder Diffraction Selected AbstractsDETERMINATION OF PIGMENTS AND BINDERS IN POMPEIAN WALL PAINTINGS USING SYNCHROTRON RADIATION , HIGH-RESOLUTION X-RAY POWDER DIFFRACTION AND CONVENTIONAL SPECTROSCOPY , CHROMATOGRAPHYARCHAEOMETRY, Issue 2 2010A. DURAN The employment of synchrotron techniques complemented by conventional laboratory systems has allowed us to deepen and improve our knowledge of Roman wall painting procedures. The palette identified in wall paintings from Pompeii and Herculaneum from the second century bc includes goethite, hematite, cinnabar, glauconite, Egyptian blue, and other components such as calcite and aragonite. Proof of the use of organic binders is provided by FTIR and PY,GC/MS. Therefore, the possibility of the use of ,a secco' techniques cannot be ruled out. Pigments in wall paintings are usually found in small percentages and conventional X-ray diffractometers do not detect them. Synchrotron radiation , high-resolution X-ray powder diffraction has allowed identification with only a few micrograms of sample. [source] Thermal, phase transition and spectral studies in erythromycin pseudopolymorphs: dihydrate and acetone solvateCRYSTAL RESEARCH AND TECHNOLOGY, Issue 12 2006Zhanzhong Wang Abstract The thermal, phase transition and spectral studies of erythromycin A dihydrate and acetone solvate were performed by Differential Scanning calorimetry (DSC), Thermo Gravimetry (TG-DTA), X-Ray Powder Diffraction (XRPD) and Fourier Transform Infra-Red (FTIR) spectrum. The non-thermal kinetic analysis of erythromycin A dihydrate was carried out by DSC at different heating rates in dynamic nitrogen atmosphere. The result showed that heating rate has substantial influence on the thermal behavior of erythromycin dihydrate. The Arrhenius parameters were estimated according to the Kissinger method. Corresponding to dehydration of dihydrate, melting of dehydrated dihydrate, phase transition from dehydrated dihydrate to anhydrate, and melting of anhydrate, the calculated activation energy were 39.60, 269.85, 261.23, and 582.16 kJmol,1, the pre-exponential factors were 3.46 × 103, 8.06 × 1032, 9.23 × 1030, and 7.29 × 1063 s,1, respectively. Ozawa method was used to compare activation energy values calculated by Kissinger method. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Observation and Characterization of Structural Phase Transitions by X-Ray Powder DiffractionPARTICLE & PARTICLE SYSTEMS CHARACTERIZATION, Issue 6 2005Wulf Depmeier Abstract Some of the basic properties of powder diffraction are summarized after a short introduction into the theory. Then it is described phenomenologically how various kinds of structural transformations affect the powder diffraction pattern. This is achieved on emphasizing that diffraction studies on powders are statistically more sound than those on single crystals, thus allowing the reliable determination of the generic properties of a given crystal structure. [source] Characterization of an Area Polluted by Copper and Zinc: the Relation between Soil Texture, Mineralogy and Pollutant ConcentrationACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 6 2009Caterina RINAUDO Abstract: Twenty-four soil samples were collected at three depths from an approximately 2.5 acre contaminated site in southern Piedmont (Italy) and then analyzed. The main soil parameters determined were: pH, Cation Exchange Capacity (CEC), particle size distribution, total organic carbon (TOC) content and retained metal concentration. The mineral phases were identified by X-Ray Powder Diffraction (XRPD). All of the samples contained Zn and Cu resulting from industrial contamination during the last century, and those obtained at depths of 20,40 cm consistently showed the highest levels. To determine which size fraction was most active in the retention process, the samples were separated into four fractions (,2 mm, ,63 ,m, ,30 ,m and ,2 ,m) and the amount of pollutant measured in each. It was found that metal retention was the highest in the clayey fraction, whose clay minerals were identified by XRPD after K+ and Mg2+ saturation, glycerol treatment and heating to 550° C. The clayey fraction was also the richest in TOC, and a direct correlation between TOC amount and metal retention was observed. [source] High-Temperature Processing of Ba3ZnTa2O9: An in situ Study Using Synchrotron X-Ray Powder Diffraction.CHEMINFORM, Issue 48 2007Phillip M. Mallinson Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] In situ X-Ray Powder Diffraction, Synthesis, and Magnetic Properties of InVO3.CHEMINFORM, Issue 9 2007Rylan J. Lundgren Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Synthesis and Crystal Structure Determination by X-Ray Powder Diffraction of Nickel Tetrametaphosphimate Octahydrate Ni2(PO2NH)4×8H2O.CHEMINFORM, Issue 43 2005S. Rebecca Roemer Abstract For Abstract see ChemInform Abstract in Full Text. [source] Thallium Selenate (Tl2SeO4) in a Paraelastic Phase by X-Ray Powder Diffraction.CHEMINFORM, Issue 27 2005Yasumitsu Matsuo Abstract For Abstract see ChemInform Abstract in Full Text. [source] Characterization of Beryllium Selenates by X-Ray Powder Diffraction, DTA and DSC.CHEMINFORM, Issue 1 2005V. G. Koleva Abstract For Abstract see ChemInform Abstract in Full Text. [source] X-Ray Powder Diffraction and 57Fe Moessbauer Spectroscopy Study on Fe0.47NbS2.CHEMINFORM, Issue 12 2003L. Ehm Abstract For Abstract see ChemInform Abstract in Full Text. [source] Synthetic Hydrocerussite, 2PbCO3×Pb(OH)2, by X-Ray Powder Diffraction.CHEMINFORM, Issue 38 2002Pauline Martinetto Abstract For Abstract see ChemInform Abstract in Full Text. [source] Hydrolysis of Pure and Sodium Substituted Calcium Aluminates and Cement Clinker Components Investigated by in Situ Synchrotron X-ray Powder DiffractionJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 8 2004Axel Nørlund Christensen The hydrolysis of pure and sodium-substituted calcium aluminates and cement clinker phases was investigated in situ in the temperature range 25°,170°C, using the angle dispersive powder synchrotron powder X-ray diffraction technique. The final hydrolysis product in all cases was Ca3Al2(OH)12. The intermediate phase Ca4Al2O7·19H2O was formed from the pure calcium aluminates, and the intermediate phases Ca4Al2O7·xH2O, x= 11, 13, or 19, were formed from the cement clinker phases. [source] The First Crystal Structures of Industrial Laked Yellow Pigments Determined by X-ray Powder DiffractionCHEMISTRY - A EUROPEAN JOURNAL, Issue 2 2009Martin For more than 100 years, laked azo pigments (i.e., dyestuff anions combined with M2+ cations) have been industrially produced, but crystal structures of commercial laked pigments have never been reported. The crystal structures of two such pigments were determined from laboratory X-ray powder data (see graphic). [source] Low temperature hydrothermal growth and optical properties of ZnO nanorodsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 1 2009J. H. Yang Abstract Well-faceted hexagonal ZnO nanorods have been synthesized by a simple hydrothermal method at relative low temperature (90°C) without any catalysts or templates. Zinc oxide (ZnO) nanorods were grown in an aqueous solution that contained Zinc chloride (ZnCl2, Aldrich, purity 98%) and ammonia (25%). Most of the ZnO nanorods show the perfect hexagonal cross section and well-faceted top and side surfaces. The diameter of ZnO nanorods decreased with the reaction time prolonging. The samples have been characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM) measurement. XRD pattern confirmed that the as-prepared ZnO was the single-phase wurtzite structure formation. SEM results showed that the samples were rod textures. The surface-related optical properties have been investigated by photoluminescence (PL) spectrum and Raman spectrum. Photoluminescence measurements showed each spectrum consists of a weak band ultraviolet (UV) band and a relatively broad visible light emission peak for the samples grown at different time. It has been found that the green emission in Raman measurement may be related to surface states. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Crystal structure refinement of the ternary compound Cu2SnTe3 by X-ray powder diffractionCRYSTAL RESEARCH AND TECHNOLOGY, Issue 4 2008G. E. Delgado Abstract The ternary compound Cu2SnTe3 crystallizes in the Imm2 (Nº 44) space group, Z = 2, with a = 12.833(4) Å, b = 4.274(1) Å, c = 6.043(1) Å, V = 331.5(1) Å3. Its structure was refined from X-ray powder diffraction data using the Rietveld method. The refinement of 25 instrumental and structural variables led to Rp = 10.2%, Rwp = 11.8%, Rexp = 7.7%, RB = 10.6%, S = 1.6 and ,2 = 2.6, for 5501 step intensities and 163 independent reflections. This compound is isostructural with Cu2GeSe3, and consists of a three-dimensional arrangement of slightly distorted CuTe4 and SnTe4 tetrahedra connected by common corners. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Crystal growth, optical and luminescence properties of (Ce,Sr)-doped PrAlO3 single crystalsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 12 2007A. Novoselov Abstract Using the micro-pulling-down method, (Ce,Sr)-doped PrAlO3 square-shaped single crystals (4×4×12 mm) were grown. Structural parameters studied by X-ray powder diffraction were consistent with R3m space group. Compositional homogeneity was checked with electron probe micro-analysis and found quite uniform. Absorption spectra and luminescence characteristics under UV and X-ray excitations were measured at room temperature with no Ce-related emission appeared. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Solvothermal growth of single-crystal hexagonal prismatic SrCO3 microrodsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 3 2007Fanglin Du Abstract Single-crystal hexagonal prism SrCO3 microrods have been prepared by a simple solvothermal route. The effects of the reaction time, the content of 1,2-propanediol and the reactants mass on the products have been investigated, respectively. The as-synthesized microrods were characterized by X-ray powder diffraction (XRD), field-emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The results reveal that the products have uniform shape and excellent monodispersity. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Growth and photorefractive properties of Mg:Ce:Cu:LiNbO3 crystals grown by Czochralski methodCRYSTAL RESEARCH AND TECHNOLOGY, Issue 8 2006Y. X. Fan Abstract In this paper, photorefractive properties of Mg:Ce:Cu:LiNbO3 crystals were studied. The crystals doped with different concentration of Mg ions have been grown by the Czochralski method. Mg concentrations in grown crystals were analyzed by an inductively coupled plasma optical emission spectrometry (ICP-OE/MS). The crystal structures were analyzed by the X-ray powder diffraction (XRD), ultraviolet-visible (UV-Vis) absorption spectra and infrared (IR) transmitatance spectra. The photorefractive properties of crystals were experimentally studied by using two-beam coupling. In this experiment we determined the writing time, maximum diffraction efficiency and the erasure time of crystals samples with He-Ne laser. The results showed that the dynamic range (M/#), sensitivity (S) and diffraction efficiency (,) were dependent on the Mg doping concentration, and the Mg(4.58mol%):Ce:Cu:LiNbO3 crystal was the most proper holographic recording media material among the six crystals studied in the paper. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Crystal structure and thermal behaviour of (Rb,Cs)BSi2O6 solid solutionsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 3 2006M. G. Krzhizhanovskaya Abstract The crystal chemistry of Rb-Cs boroleucites has been studied by means of X-ray powder diffraction at room and elevated temperatures. The cubic I-43d , cubic Ia3d phase transition was investigated using a series of samples prepared by solid-state reaction along the pseudobinary system RbBSi2O6 - CsBSi2O6. The Rietveld refinement of the structures of Rb1-xCsxBSi2O6 solid solutions (x = 0.2, 0.4, 0.6, 0.8) demonstrates that the solutions with a high Rb content crystallise in the cubic I-43d space group, and the boroleucites with a considerable Cs content have Ia3d symmetry. Rb can substitute Cs in a wide range of compositions. Within a narrow range of x = 0.5 - 0.6 immiscibility was revealed. Under Rb-Cs substitution the cubic lattice parameter, the (Rb,Cs)-O distances, and the angles between tetrahedra of the I-43d phase change clearly, while those of the Ia3d phase change slightly. The HTXRD data shows that the I-43d phase transforms into a Ia3d phase on heating analogously to a change of the composition. As the Cs content increases the transition temperature decreases. The low temperature I-43d phase shows a higher thermal expansion than the high temperature Ia3d phase. © 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim [source] Rapid crystal growth without inherent supersaturation induced by nanoscale fluid flows?CRYSTAL RESEARCH AND TECHNOLOGY, Issue 1 2006M. J. Jones Abstract Crystal growth is a process that only takes place under non-equilibrium conditions and a necessary prerequisite is that the crystal is exposed to a phase that is supersaturated in the material the crystal is composed of, be it a solution, a vapour or a supercooled melt. In industrial mass crystallization the growth rate for a population of crystals (in suspension growth processes [1]) rarely exceeds mean linear velocities of 10 -7 ms -1. Here we present a mass crystallization process which is accompanied by rapid crystal growth several orders of magnitude faster and into a region of solution that is without inherent supersaturation. The material investigated is a solid hydrate that exhibits a solution mediated phase transition to its anhydrous form in the presence of methanol [2]. The phase transition is initiated simply by placing an amount of hydrate crystals into the solvent and is characterized by the rapid emergence of needle-shaped crystals. The needles emanate from the crystal faces of the hydrate crystals and grow into the solution, which is nominally free of the substance to be crystallized. The high growth rate of the crystals, which of the order of up to 10 -4 ms -1 is surprising. Although rapid needle growth has been observed before [3-9], to date a satisfactory explanation for needles growing under the abovementioned conditions is still outstanding. Based upon the topology of the crystals we propose a tentative mechanism for this phenomenon capable of explaining the unusually rapid growth and highlight those questions that need addressing in order to verify this mechanism. X-ray powder diffraction is used to characterize the crystal phase of the needles; confocal fluorescence microscopy reveals that the needles are hollow. The width of these needles is between 0.5 and 5 ,m, their length appears to be limited only by the amount of hydrate available for their formation. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Synthesis and characterization of compounds LixMn1+xFe2,2xO4 with spinel structure in the quasiternary system "LiO0,5 , MnOx , FeOx"CRYSTAL RESEARCH AND TECHNOLOGY, Issue 1 2006C. Wende Abstract The thermal decomposition of freeze-dried Li-Mn(II)-Fe(III)-formate precursors was investigated by means of DTA, TG and mass spectroscopy. By the thermal treatment of the prefired precursors between 400 and 1000°C, single phase solid solutions LixMn1+xFe2,2xO4 (0 , x , 1) with cubic spinel structure were obtained. To get single phase spinels, special conditions concerning the temperature T and the oxygen partial pressure p(O2) during the synthesis are required. Because of the high reactivity of the freeze-dried precursors, in comparison with the conventional solid state reaction, the reaction temperature can be lowered by 200°C. The cation distribution and the properties of the Li-Mn-ferrites were studied by chemical analysis, X-ray powder diffraction and magnetization measurements. It was found that for high substitution rates, almost all lithium occupies the tetrahedral coordinated A-sites of the spinel lattice AB2O4, while at small x-values, lithium ions are distributed over the tetrahedral and octahedral sites. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Synthesis, spectroscopic studies and ab-initio structure determination from X-ray powder diffraction of bis-(N-3-acetophenylsalicylaldiminato)copper(II)CRYSTAL RESEARCH AND TECHNOLOGY, Issue 8 2005S. Banerjee Abstract The synthesis, spectroscopic studies and crystal structure determination from X-ray powder diffraction have been carried out for bis-(N-3-acetophenylsalicylaldiminato)copper(II). The structure is triclinic, space group P1 with unit cell dimensions a = 11.817(1) Å, b = 12.087(1) Å, c = 9.210(1) Å, , = 102.62(1)°, , = 111.16(1)°, , = 86.15(1)°, V = 1197.0(2)Å3, Z = 2. The structure has been solved by Monte Carlo simulated annealing approach and refined by GSAS package. The final Rp value was 8.68%. The coordination geometry around the copper atom in the complex is intermediate between square-planar and tetrahedral with two salicylaldimine ligands in trans arrangement. Intermolecular C,H,O hydrogen bonds between molecules related by translation generate infinite chains along [010] direction. The molecular chains are linked via additional C,H,O hydrogen bonds to form a three-dimensional supramolecular network. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] PbS crystals with clover-like structure: Preparation, characterization, optical properties and influencing factorsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 3 2004Yonghong Ni Abstract A new and simple route to synthesize Lead sulfide (PbS) crystals with the clover-like structure was described in the current paper. PbS was prepared in a simple aqueous solution employing (CH3COO)2Pb and thiourea as the initial materials under 130 W microwave irradiation. No any surfactant or template including organic polyamines with N-chelation property was needed. The phase and composition of the product were identified by X-ray powder diffraction (XRD) and X-ray photoelectron spectra (XPS). TEM observation showed that the product with the six-petal flower-shaped structures was obtained, but SEM observation confirmed the clover-like structure of the product; and the six-petal flowers were formed via the overlap of two clovers revolved 60° around the center of the flower. Some factors affected the shape of the final product were studied and the optical properties of PbS crystals with the clover-like structure were measured. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Studies on the growth and optical characterization of dysprosium gadolinium oxalate single crystalsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 2 2004A. Elizebeth Abstract Preparation and optical characterization of dysprosium gadolinium oxalate (DGO) single crystal is reported. The crystals were grown using silica gel technique, by the controlled reaction of rare earth nitrates with oxalic acid. Crystals were characterized using X-ray powder diffraction, optical absorption and fluorescence studies. Radiative transition probability, fluorescence branching ratio and radiative lifetime of Dy3+ in the crystal are evaluated by the parameterization of the absorption spectrum by the Judd-Ofelt theory. The recorded fluorescence spectrum showed two well resolved peaks at 480 nm and 571 nm and are assigned to the transitions from 4F9/2 , 6H15/2 and 6H13/2 of Dy3+. Stimulated emission crossection and optical gain of these transitions are also evaluated. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Mechanical activation of precursors for nanocrystalline materialsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 1 2003H. Heegn Abstract Nanostructured materials win big scientific interest and increasingly economic meaning through their specific exceptional properties. Precursors that were compacted by pressing and sintering are normally used preparation of materials. In present work, the influence of mechanical activation by grinding on the structure as well as on compacting and sintering behavior of oxides from magnesium, aluminium and silicon has been investigated. Starting materials for each metal oxide differ in microstructure, dispersity, and porosity. The influence of mechanical activation on the destruction of crystalline structure to nanocrystalline, as well as to the amorphous stage and the compaction of powders with nano-particles, as well as structures with nanoscale pores have been compared. The possibilities of the consolidation of nanostructured materials were investigated. The mechanical activation took place in a disc vibration mill. The mechanical activated materials as well as their pressing and their sintering products were characterized by density, particle-sizedistribution, specific surface, pore-structure, microstructure, and crystallite size by X-ray powder diffraction (XRD). The mechanical activation of the model-substances led, in most cases, to an improvement of the compaction properties; thus, this improvement can be achieved with subsequent sintering densities up to 98% of the theoretical density. From these experiments, generalizations transferable to other materials can be made. [source] Crystal growth of some urinary stone constituents: II.CRYSTAL RESEARCH AND TECHNOLOGY, Issue 12 2002In-vitro crystallization of hippuric acid Abstract Hippuric acid [C6H5CONHCH2COOH], one of the organic chemical constituents of urinary stone is crystallized in silica gel under suitable pH conditions by double diffusion method. The grown crystals were characterized by density measurement, Fourier transform infrared spectroscopy, X-ray powder diffraction and thermogravimetric analysis. [source] Ultrasound-Assisted Synthesis of CuO Nanorods in a Neat Room-Temperature Ionic LiquidEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 19 2009Tarek Alammar Abstract CuO nanorods were prepared via ultrasound-assisted synthesis in the room temperature ionic liquid (RTIL) 1-butyl-3-methylimidazoliumbis(trifluoromethylsulfonyl)imide [C4mim][Tf2N] as a reaction medium. The structure and morphology of CuO nanorods were characterized with X-ray powder diffraction (XRD), transmission electron microscopy (TEM), energy-dispersive X-ray analysis (EDX), X-ray photoelectron spectroscopy (XPS), vibrational and UV/Vis absorption spectroscopy. The synthesized CuO nanocrystals are of rod like shape with lengths from 30 to 100 nm and diameters of about 10 nm. Quantum size effects were observed as the bandgap of the CuO nanorods was determined to 2.41 eV from UV/Vis absorption measurements, which is significantly larger than the bulk value. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Organometallic Access to Intermetallic , -CuE2 (E = Al, Ga) and Cu1,xAlx PhasesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 21 2008Mirza Cokoja Abstract In this work, we compare different precursor approaches for the mild decomposition to copper,aluminum and ,gallium powder materials in nonaqueous solution. Referring to previous work on the preparation of Cu,Al alloy materials from [(AlCp*)4] and [CpCu(PMe3)], the amine-stabilized metal trihydrides [(Me3N)AlH3] and [(quinuclidine)GaH3] were used as alternative sources for Al and Ga. In a comparative study, [(Me3N)AlH3] and [(AlCp*)4] were treated with the Cu precursors [CpCu(PMe3)] and [{Cu(mesityl)}5] in mesitylene solution in various molar ratios at 150 °C and 3 bar H2 to give metallic precipitates of the composition Cu1,xAlx (x = 0.67, 0.50, 0.31). Whereas the combination [(AlCp*)4] with [{Cu(mesityl)}5] did not yield an intermetallic phase, all other Cu/Al precursor combinations led to alloyed Cu,Al materials. For x = 0.67, the ,-CuAl2 phase formed, as shown by X-ray powder diffraction (XRD) and solid-state magic-angle-spinning (MAS)NMR spectroscopic studies. Similarly, the reaction of [{Cu(mesityl)}5] with [(quinuclidine)GaH3] immediately led to the precipitation of a gray powder, without the addition of hydrogen. The powder was identified by means of XRD as ,-CuGa2. At x = 0.50 and below, the reactions were less phase selective depending on the precursor combination. [CpCu(PMe3)] combined with both Al precursors afforded a mixture of several Cu,Al phases, whereas [{Cu(mesityl)}5] was treated with [(Me3N)AlH3] to yield a material whose X-ray signature was assigned to the monoclinic Cu0.51Al0.49 phase. The ,-Cu9Al4 phase could not be obtained from [CpCu(PMe3)]; instead, solid solutions of ,-Cu were obtained. The treatment of [{Cu(mesityl)}5] with [(Me3N)AlH3] in the Cu/Al molar ratio of 9:4 (x = 0.31) gave a gray powder, which could be identified by XRD as ,-Cu9Al4.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Quenching the Hysteresis in Single Crystals of a 1D Chain Iron(II) Spin Crossover ComplexEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 19 2008Birgit Weber Abstract The unusual grinding effects observed in the 1D spin crossover polymer [FeL(bipy)]n (1), with L being a tetradentate N2O22, coordinating Schiff base type ligand {(3,3,)-[1,2-phenylenebis(iminomethylidyne)]bis(2,4-pentanedionato)(2,)- N,N,,O2,O2,} and bipy = 4,4,-bipyridine, are investigated using magnetic measurements, X-ray powder diffraction and optical reflectivity studies. The observed behaviour can be explained when solvent effects are taken into account. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Guest-Inclusion Behavior of Double-Strand 1D Coordination Polymers Based on N,N, -Type Schiff Base LigandsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 10 2008Qing Wang Abstract Four double-strand one-dimensional (1D) coordinationpolymers, namely, {[Ni(N3Py)2(NO3)2]·(C6H6)x·C2H5OH}n (1), [Cd(ImBNN)2(CH3C6H4SO3)2]n (2), {[Co(N3OPy)2(H2O)2](ClO4)2·C6H6·H2O}n (3), and {[Co(N3OPy)2(H2O)2](ClO4)2·(C8H10)x}n (4) were obtained from the assembly of three N,N, -type Schiff base ligands, 1,4-bis(3-pyridyl)-2,3-diaza-1,3-butadiene (N3Py), 2,5-bis(4,-(imidazol-1-yl)benzyl)-3,4-diaza-2,4-hexadiene (ImBNN), and bis[4-(3-pyridylmethylenemino)phenoxy]methane (N3OPy), with transition-metal ions. All complexes were characterized by single-crystal X-ray diffraction, X-ray powder diffraction, and FTIR measurements. The guest-inclusion behavior of these complexes were investigated by thermogravimetric and X-ray powder diffraction analyses. The structural relationship between the ligands and the cavity sizes and packing fashions have been discussed to elucidate the distinctive guest-inclusion behavior of these complexes.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] | ||||||||||||||||||||||||||||||||||