ChemInform Abstract: High-Precision X-Ray Diffraction Data, Experimental and Theoretical Study of 2H-MoS2.

Conventional SAD patterns as obtained in the TEM present difficulties for identification of materials such as asbestiform minerals, although diffraction data is considered to be an important method for making this purpose. The preferred orientation of the fibers and the spotty patterns that are obtained do not readily lend themselves to measurement of the integrated intensity values for each d-spacing, and even the d-spacings may be hard to determine precisely because the true center location for the broken rings requires estimation. We have implemented an automatic method for diffraction pattern measurement to overcome these problems. It automatically locates the center of patterns with high precision, measures the radius of each ring of spots in the pattern, and integrates the density of spots in that ring. The resulting spectrum of intensity vs. radius is then used just as a conventional X-ray diffractometer scan would be, to locate peaks and produce a list of d,I values suitable for search/match comparison to known or expected phases.

Download Full-text

High-pressure synthesis and crystal structure of the mixed-cation borate Ga4In4B15O33(OH)3

Zeitschrift für Naturforschung B ◽

10.1515/znb-2019-0014 ◽

2019 ◽

Vol 74 (4) ◽

pp. 357-363

Author(s):

Daniela Vitzthum ◽

Hubert Huppertz

Keyword(s):

Crystal Structure ◽

High Pressure ◽

High Temperature ◽

Diffraction Data ◽

X Ray Diffraction ◽

Synthesis And Crystal Structure ◽

X Ray ◽

Mixed Cation ◽

High Pressure High Temperature ◽

Pressure Synthesis

AbstractThe mixed cation triel borate Ga4In4B15O33(OH)3 was synthesized in a Walker-type multianvil apparatus at high-pressure/high-temperature conditions of 12.5 GPa and 1300°C. Although the product could not be reproduced in further experiments, its crystal structure could be reliably determined via single-crystal X-ray diffraction data. Ga4In4B15O33(OH)3 crystallizes in the tetragonal space group I41/a (origin choice 2) with the lattice parameters a = 11.382(2), c = 15.244(2) Å, and V = 1974.9(4) Å3. The structure of the quaternary triel borate consists of a complex network of BO4 tetrahedra, edge-sharing InO6 octahedra in dinuclear units, and very dense edge-sharing GaO6 octahedra in tetranuclear units.

Download Full-text

Crystallization and preliminary x-ray diffraction data of the cryptomonad biliprotein phycocyanin-645 from a Chroomonas spec.

Archives of Microbiology ◽

10.1007/bf00454927 ◽

1984 ◽

Vol 140 (2-3) ◽

pp. 202-205 ◽

Cited By ~ 14

Author(s):

Walter Morisset ◽

Werner Wehrmeyer ◽

Tilman Schirmer ◽

Wolfram Bode

Keyword(s):

Diffraction Data ◽

X Ray Diffraction ◽

X Ray

Download Full-text

Theoretically derived thermodynamic properties can be improved by the refinement of low-frequency modes against X-ray diffraction data

Chemical Communications ◽

10.1039/d1cc02608a ◽

2021 ◽

Author(s):

Anna Agnieszka Hoser ◽

Marcin Sztylko ◽

Damian Trzybiński ◽

Anders Østergaard Madsen

Keyword(s):

Thermodynamic Properties ◽

Dft Calculations ◽

Diffraction Data ◽

Molecular Crystals ◽

Low Frequency ◽

X Ray Diffraction ◽

X Ray ◽

Efficient Approach

A framework for estimation of thermodynamic properties for molecular crystals via refinement of frequencies from DFT calculations against X-ray diffraction data is presented. The framework provides an efficient approach to...

Download Full-text

Transient phase fraction and dislocation density estimation from in-situ X-ray diffraction data with a low signal-to-noise ratio using a Bayesian approach to the Rietveld analysis

Materials Characterization ◽

10.1016/j.matchar.2020.110860 ◽

2020 ◽

pp. 110860

Author(s):

Manfred Wiessner ◽

Paul Angerer ◽

Sybrand van der Zwaag ◽

Ernst Gamsjäger

Keyword(s):

Dislocation Density ◽

Density Estimation ◽

Diffraction Data ◽

Signal To Noise Ratio ◽

Rietveld Analysis ◽

Transient Phase ◽

X Ray Diffraction ◽

Signal To Noise ◽

X Ray

Download Full-text

Single-crystal investigation of Ce5AgxGe4−x (x = 0.1−1.08) with Sm5Ge4 type

Zeitschrift für Naturforschung B ◽

10.1515/znb-2020-0091 ◽

2020 ◽

Vol 75 (8) ◽

pp. 765-768

Author(s):

Bohdana Belan ◽

Dorota Kowalska ◽

Mariya Dzevenko ◽

Mykola Manyako ◽

Roman Gladyshevskii

Keyword(s):

Crystal Structure ◽

Single Crystal ◽

Diffraction Data ◽

Binary Compound ◽

Lattice Parameters ◽

X Ray Diffraction ◽

Space Group ◽

X Ray

AbstractThe crystal structure of the phase Ce5AgxGe4−x (x = 0.1−1.08) has been determined using single-crystal X-ray diffraction data for Ce5Ag0.1Ge3.9. This phase is isotypic with Sm5Ge4: space group Pnma (No. 62), Pearson code oP36, Z = 4, a = 7.9632(2), b = 15.2693(5), c = 8.0803(2) Å; R1 = 0.0261, wR2 = 0.0460, 1428 F2 values and 48 variables. The two crystallographic positions 8d and 4c show Ge/Ag mixing, leading to a slight increase in the lattice parameters as compared to those of the pure binary compound Ce5Ge4.

Download Full-text

The modulated structure of Bi2Sr3−xCaxCu2O8: A commensurate model from single crystal X-ray diffraction data

Physica C Superconductivity ◽

10.1016/0921-4534(89)90396-1 ◽

1989 ◽

Vol 161 (5-6) ◽

pp. 598-606 ◽

Cited By ~ 49

Author(s):

G. Calestani ◽

C. Rizzoli ◽

M.G. Francesconi ◽

G.D. Andreetti

Keyword(s):

Single Crystal ◽

Diffraction Data ◽

X Ray Diffraction ◽

Modulated Structure ◽

X Ray

Download Full-text

Crystallographic features of ammonium fluoroelpasolites: dynamic orientational disorder in crystals of (NH4)3HfF7 and (NH4)3Ti(O2)F5

Acta Crystallographica Section B Structural Science Crystal Engineering and Materials ◽

10.1107/s2052520616017534 ◽

2017 ◽

Vol 73 (1) ◽

pp. 1-9 ◽

Cited By ~ 5

Author(s):

Anatoly A. Udovenko ◽

Alexander A. Karabtsov ◽

Natalia M. Laptash

Keyword(s):

Single Crystal ◽

Electron Density ◽

Diffraction Data ◽

Central Atom ◽

X Ray Diffraction ◽

Dynamic Nature ◽

Orientational Disorder ◽

High Quality ◽

Structural Units ◽

X Ray

A classical elpasolite-type structure is considered with respect to dynamically disordered ammonium fluoro-(oxofluoro-)metallates. Single-crystal X-ray diffraction data from high quality (NH4)3HfF7 and (NH4)3Ti(O2)F5 samples enabled the refinement of the ligand and cationic positions in the cubic Fm \bar 3 m (Z = 4) structure. Electron-density atomic profiles show that the ligand atoms are distributed in a mixed (split) position instead of 24e. One of the ammonium groups is disordered near 8c so that its central atom (N1) forms a tetrahedron with vertexes in 32f. However, a center of another group (N2) remains in the 4b site, whereas its H atoms (H2) occupy the 96k positions instead of 24e and, together with the H3 atom in the 32f position, they form eight spatial orientations of the ammonium group. It is a common feature of all ammonium fluoroelpasolites with orientational disorder of structural units of a dynamic nature.

Download Full-text