scholarly journals Synthesis, Crystal Structure, and Thermal Properties of CaSO4·2H2O Single Crystals

2015 ◽  
Vol 7 (2) ◽  
pp. 12 ◽  
Author(s):  
Takanori Fukami ◽  
Shuta Tahara ◽  
Keiko Nakasone ◽  
Chitoshi Yasuda
Keyword(s):  
Crystal Structure ◽  
Weight Loss ◽  
Single Crystals ◽  
Water Molecules ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Agar Gel ◽  
X Ray ◽  
Calcium Sulfate Dihydrate ◽  
White Substance

Single crystals were grown at room temperature from the precursors CaCO3 and NH2SO3H by a gel method using agar-agar gel as the medium of growth. Differential scanning calorimetry, thermogravimetric–differential thermal analysis, and X-ray diffraction measurements were performed on the single crystals. The crystal structure of the grown crystals was confirmed to be very similar to that of calcium sulfate dihydrate (CaSO4·2H2O, gypsum). The temperature at which dehydration and evaporation of intercalated water molecules in the single crystal occurred was found to be 375.9 K, which was very close to that in CaSO4·2H2O. From all these results, we identified the grown single crystals as CaSO4·2H2O. The weight loss owing to the thermal decomposition of anhydrous CaSO4 formed by the dehydration of the single gypsum crystals was found to occur at ~1530 K. This weight loss was probably caused by the evolution of SO3 gas by sublimation, and the chalky white substance left in the open vessel after decomposition was calcium oxide (CaO).

scholarly journals Thermal Properties and Crystal Structure of BaC4H4O6 Single Crystals

2016 ◽  
Vol 9 (1) ◽  
pp. 30
Author(s):  
Takanori Fukami ◽  
Seiya Hiyajyo ◽  
Shuta Tahara ◽  
Chitoshi Yasuda
Keyword(s):  
Crystal Structure ◽  
Single Crystals ◽  
Room Temperature ◽  
Decomposition Product ◽  
Structural Parameters ◽  
Group Symmetry ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Weight Losses

Single crystals of barium L-tartrate, BaC4H4O6, were grown at 308 K by a gel method using silica gel as the growth medium. Differential scanning calorimetry, thermogravimetric-differential thermal analysis, and X-ray diffraction measurements were performed on the single crystals. The space group symmetry (orthorhombic, P212121) and structural parameters were determined at room temperature. The crystal structure consisted of BaO9 polyhedra, C4H4O6 molecules, and zig-zag hydrogen-bonded chains along the a- and c-axes linked by O–H···O and C–H···O hydrogen bonds between adjacent molecules. Weight losses due to thermal decomposition of BaC4H4O6 occurred in the temperature range of 450–1530 K. We suggest that the evolution of 2H2, 2CO, CO, (1/2)O2, and O2 gases caused the observed weight losses and that the decomposition product, barium monocarbide BaC, formed a residue in the vessel.

scholarly journals Some Novel Cobalt Diphenylphosphine Complexes: Synthesis, Characterization, and Behavior in the Polymerization of 1,3-Butadiene

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 4067
Author(s):  
Giovanni Ricci ◽  
Giuseppe Leone ◽  
Giorgia Zanchin ◽  
Benedetta Palucci ◽  
Alessandra Forni ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Single Crystals ◽  
The Novel ◽  
X Ray Diffraction ◽  
X Ray ◽  
And Behavior

Some novel cobalt diphenylphosphine complexes were synthesized by reacting cobalt(II) chloride with (2-methoxyethyl)diphenylphosphine, (2-methoxyphenyl)diphenylphosphine, and 2-(1,1-dimethylpropyl)-6-(diphenylphosphino)pyridine. Single crystals suitable for X-ray diffraction studies were obtained for the first two complexes, and their crystal structure was determined. The novel compounds were then used in association with methylaluminoxane (MAO) for the polymerization of 1,3-butadiene, and their behavior was compared with that exhibited in the polymerization of the same monomer by the systems CoCl2(PnPrPh2)2/MAO and CoCl2(PPh3)2/MAO. Some significant differences were observed depending on the MAO/Co ratio used, and a plausible interpretation for such a different behavior is proposed.

scholarly journals Synthesis and Complexation Properties of 2-Hydroxy-5-methoxyphenylphosphonic Acid (H3L1). Crystal Structure of the [Cu(H2L1)2(Н2О)2] Complex

2021 ◽  
Vol 91 (11) ◽  
pp. 2176-2186
Author(s):  
G. S. Tsebrikova ◽  
Yu. I. Rogacheva ◽  
I. S. Ivanova ◽  
A. B. Ilyukhin ◽  
V. P. Soloviev ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Methoxy Group ◽  
Protonation Constants ◽  
Water Molecules ◽  
X Ray Diffraction ◽  
X Ray ◽  
The Stability ◽  
Intramolecular Hydrogen ◽  
Oxygen Atoms

Abstract 2-Hydroxy-5-methoxyphenylphosphonic acid (H3L1) and the complex [Cu(H2L1)2(H2O)2] were synthesized and characterized by IR spectroscopy, thermogravimetry, and X-ray diffraction analysis. The polyhedron of the copper atom is an axially elongated square bipyramid with oxygen atoms of phenolic and of monodeprotonated phosphonic groups at the base and oxygen atoms of water molecules at the vertices. The protonation constants of the H3L1 acid and the stability constants of its Cu2+ complexes in water were determined by potentiometric titration. The protonation constants of the acid in water are significantly influenced by the intramolecular hydrogen bond and the methoxy group. The H3L1 acid forms complexes CuL‒ and CuL24‒ with Cu2+ in water.

scholarly journals Rubidium tetrafluoridobromate(III): redetermination of the crystal structure from single-crystal X-ray diffraction data

IUCrData ◽  
2019 ◽  
Vol 4 (11) ◽  
Author(s):  
Artem V. Malin ◽  
Sergei I. Ivlev ◽  
Roman V. Ostvald ◽  
Florian Kraus
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Single Crystals ◽  
Diffraction Data ◽  
Structure Type ◽  
X Ray Diffraction ◽  
X Ray ◽  
Square Planar ◽  
Atomic Coordinates

Single crystals of rubidium tetrafluoridobromate(III), RbBrF4, were grown by melting and recrystallizing RbBrF4 from its melt. This is the first determination of the crystal structure of RbBrF4 using single-crystal X-ray diffraction data. We confirmed that the structure contains square-planar [BrF4]− anions and rubidium cations that are coordinated by F atoms in a square-antiprismatic manner. The compound crystallizes in the KBrF4 structure type. Atomic coordinates and bond lengths and angles were determined with higher precision than in a previous report based on powder X-ray diffraction data [Ivlev et al. (2015). Z. Anorg. Allg. Chem. 641, 2593–2598].

Crystal Structure of Calcium Picrate Pentahydrate: A New Eight-Coordinate Stereochemistry for [M(bidentate)2(unidentate)4]

1979 ◽  
Vol 32 (2) ◽  
pp. 301 ◽  
Author(s):  
V Diakiw ◽  
TW Hambley ◽  
DL Kepert ◽  
CL Raston ◽  
AH White
Keyword(s):  
Crystal Structure ◽  
Water Molecule ◽  
Single Crystal ◽  
Title Compound ◽  
Lattice Site ◽  
The Other ◽  
Water Molecules ◽  
X Ray Diffraction ◽  
Triangular Face ◽  
X Ray

The crystal structure of the title compound, Ca(C6H2N307)2,5H2O, has been determined by single-crystal X-ray diffraction at 295(1) K and refined by least squares to a residual of 0.049 for 1513 'observed' reflections. Crystals are orthorhombic, Pmab, a 24.169(6), b l0.292(7), c 8.554(2) �, Z 4. The stereochemistry about the calcium has not been observed previously for the system [M(bidentate)2- (unidentate)4]; in the present structure, the calcium is coordinated by a pair of bidentate picrate ligands and the four water molecules in an array in which three of the water molecules occupy a triangular face of a square antiprism, the overall array having m symmetry. The remaining water molecule occupies a lattice site with no close interaction with the other species.

Synthesis, crystal structure, and vibrational spectra of the complex maleic acid•2H2O•18-crown-6

1990 ◽  
Vol 68 (12) ◽  
pp. 2183-2189 ◽  
Author(s):  
Pierre Audet ◽  
Rodrigue Savoie ◽  
Michel Simard
Keyword(s):  
Crystal Structure ◽  
Water Molecule ◽  
Maleic Acid ◽  
Water Molecules ◽  
Infrared And Raman Spectra ◽  
X Ray Diffraction ◽  
Monoclinic System ◽  
X Ray ◽  
O 18 ◽  
Stoichiometric Complex

A stoichiometric complex of formula maleic acid•2H2O•18-crown-6 has been obtained from maleic acid and the macrocyclic polyether 18-crown-6. Crystals of this complex have been shown by X-ray diffraction crystallography to belong to the Cc space group of the monoclinic system. The acid molecules in the adduct are linked to each other through a water molecule, giving infinite [-acid-H2O-]n chains. They are also linked to the crown ether via water molecules. The infrared and Raman spectra of the complex are presented and compared to those of crystalline maleic acid. Keywords: maleic acid/18-crown-6, structure, X-ray, spectra.

Study of thermal properties of Ga0.5In1.5Se3 by differential scanning calorimetry

2021 ◽  
pp. 2150407
Author(s):  
S. I. Ibrahimova
Keyword(s):  
Crystal Structure ◽  
Differential Scanning Calorimetry ◽  
Thermal Properties ◽  
Thermal Effects ◽  
Room Temperature ◽  
Structural Studies ◽  
X Ray Diffraction ◽  
Hexagonal Symmetry ◽  
Scanning Calorimetry ◽  
X Ray

The crystal structure and thermal properties of the [Formula: see text] compound have been investigated. Structural studies were performed by X-ray diffraction at room temperature. The crystal structure of this compound was found to correspond to the hexagonal symmetry of the space group P61. Thermal properties were studied using a differential scanning calorimetry (DSC). It was found in the temperature range [Formula: see text] that thermal effects occur at temperatures [Formula: see text] and [Formula: see text]. The thermodynamic parameters of these effects are calculated.

The new barium compound Ba4Al7+x: formation and crystal structure

2016 ◽  
Vol 71 (5) ◽  
pp. 611-619 ◽  
Author(s):  
Yurii Prots ◽  
Felix Lange ◽  
Christina Drathen ◽  
Marcus Schmidt ◽  
Yuri Grin
Keyword(s):  
Crystal Structure ◽  
Structural Model ◽  
Model Space ◽  
Binary Compound ◽  
Formation Temperature ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Laves Phases ◽  
X Ray

AbstractCombining laboratory X-ray powder diffraction with in-situ high-temperature synchrotron experiments and differential scanning calorimetry, it has been shown that Ba21Al40, Ba3Al5, Ba7Al10 and Ba4Al5 decompose peritectically at 914, 826, 756, and 732°C, respectively. In addition, a new binary compound with the composition Ba4Al7+x (x = 0.17) and the formation temperature of 841°C was found. The initial structural model (space group P63/mmc, a = 6.0807(1), c = 39.2828(8) Å) with four Ba and five Al crystallographic positions was developed. It is based on the intergrowth concept involving the neighboring Ba21Al40 and Ba3Al5 phases and the derived atomic arrangement is subsequently refined using X-ray diffraction data. The crystal structures of all phases in the Ba–Al system, except BaAl4, exhibit Kagomé nets of aluminum atoms resembling those observed for the B atoms in the Laves phases AB2. In the crystal structure of Ba4Al7+x, single Kagomé layers alternate with double slabs (MgZn2 motif) along [001] and are separated by Ba cations. Intergrowth features of Ba4Al7+x are discussed together with the neighboring Ba–Al compounds and Sr5Al9.

scholarly journals Synthesis and Crystal Structure of the Bioinorganic Complex [Sb(Hedta)]·2H2O

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Di Li ◽  
Guo-Qing Zhong
Keyword(s):  
Crystal Structure ◽  
Ethylenediaminetetraacetic Acid ◽  
Raw Materials ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Cell Parameters ◽  
Composition And Structure ◽  
Decomposition Processes ◽  
Distorted Trigonal Bipyramid

The antimony(III) complex [Sb(Hedta)]·2H2O was synthesized with ethylenediaminetetraacetic acid (H4edta) and antimonous oxide as main raw materials in aqueous solution. The composition and structure of the complex were characterized by elemental analysis, infrared spectra, single crystal X-ray diffraction, X-ray powder diffraction, thermogravimetry, and differential scanning calorimetry. The crystal structure of the antimony(III) complex belongs to orthorhombic system, space group Pna2(1), with cell parameters ofa=18.4823(18) Å,b=10.9408(12) Å,c=7.3671(5) Å,V=1489.7(2) Å3,Z=4, andDc=1.993 g cm−3. The Sb(III) ion is five-coordinated by two amido N atoms and three carboxyl O atoms from a single Hedta3−ligand, forming a distorted trigonal bipyramid geometry. The thermal decomposition processes of the complex include dehydration, oxidation, and pyrolysis of the ligand, and the last residue is Sb2O3at the temperature of 570°C.

scholarly journals Crystal structure, homogeneity range and electronic structure of rhombohedral γ-Mn5Al8

2017 ◽  
Vol 232 (7-9) ◽  
Author(s):  
Srinivasa Thimmaiah ◽  
Zachary Tener ◽  
Tej N. Lamichhane ◽  
Paul C. Canfield ◽  
Gordon J. Miller
Keyword(s):  
Crystal Structure ◽  
Phase Diagram ◽  
Electronic Structure ◽  
Single Crystal ◽  
Single Crystals ◽  
Homogeneity Range ◽  
X Ray Diffraction ◽  
X Ray ◽  
Eds Analysis

AbstractThe γ-region of the Mn–Al phase diagram between 45 and 70 at.% Al was re-investigated by a combination of powder and single crystal X-ray diffraction as well as EDS analysis to establish the distribution of Mn and Al atoms. Single crystals of γ-Mn

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