scholarly journals Topological analysis of vanadium borides from high-resolution single-crystal diffraction data

2009 ◽  
Vol 65 (a1) ◽  
pp. s226-s227
Author(s):  
Bürgehan Terlan ◽  
Horst Borrmann ◽  
Yuri Grin
Keyword(s):  
High Resolution ◽  
Single Crystal ◽  
Diffraction Data ◽  
Topological Analysis ◽  
Single Crystal Diffraction ◽  
Resolution Single

Calculation of electrostatic potentials from multipole charge densities

1993 ◽  
Vol 208 (2) ◽  
Author(s):  
Hendrik L. De Bondt ◽  
N. M. Blaton ◽  
O. M. Peeters ◽  
C. J. De Ranter
Keyword(s):  
High Resolution ◽  
Single Crystal ◽  
Charge Density ◽  
Electrostatic Potential ◽  
Electron Distribution ◽  
Density Model ◽  
Slater Type ◽  
Single Crystal Diffraction ◽  
Charge Densities ◽  
Resolution Single

AbstractA rigorous analytical expression is derived for the electrostatic potential originating from aspherical atomic multipole electron densities according to the Stewart or Hansen-Coppens charge density model with a Slater type radial electron distribution. Such models are widely used to determine charge distributions from high resolution single crystal diffraction experiments.

Combined high resolution powder and single-crystal diffraction to determine the structure of Li1+xCeIIIxCeIV6-xF25

2007 ◽  
Vol 2007 (suppl_26) ◽  
pp. 455-460 ◽  
Author(s):  
G. Renaudin ◽  
E. Mapemba ◽  
M. El-Ghozzi ◽  
M. Dubois ◽  
D. Avignant ◽  
...  
Keyword(s):  
High Resolution ◽  
Single Crystal ◽  
Single Crystal Diffraction

Thermal-induced transformation of glutamic acid to pyroglutamic acid and self-cocrystallization: a charge–density analysis

2022 ◽  
Vol 78 (2) ◽  
Author(s):  
Sehrish Akram ◽  
Arshad Mehmood ◽  
Sajida Noureen ◽  
Maqsood Ahmed
Keyword(s):  
Hydrogen Bonds ◽  
Glutamic Acid ◽  
Single Crystal ◽  
Diffraction Data ◽  
Density Functional ◽  
Quantitative Estimation ◽  
Topological Analysis ◽  
Pyroglutamic Acid ◽  
X Ray Diffraction ◽  
X Ray

Thermal-induced transformation of glutamic acid to pyroglutamic acid is well known. However, confusion remains over the exact temperature at which this happens. Moreover, no diffraction data are available to support the transition. In this article, we make a systematic investigation involving thermal analysis, hot-stage microscopy and single-crystal X-ray diffraction to study a one-pot thermal transition of glutamic acid to pyroglutamic acid and subsequent self-cocrystallization between the product (hydrated pyroglutamic acid) and the unreacted precursor (glutamic acid). The melt upon cooling gave a robust cocrystal, namely, glutamic acid–pyroglutamic acid–water (1/1/1), C5H7NO3·C5H9NO4·H2O, whose structure has been elucidated from single-crystal X-ray diffraction data collected at room temperature. A three-dimensional network of strong hydrogen bonds has been found. A Hirshfeld surface analysis was carried out to make a quantitative estimation of the intermolecular interactions. In order to gain insight into the strength and stability of the cocrystal, the transferability principle was utilized to make a topological analysis and to study the electron-density-derived properties. The transferred model has been found to be superior to the classical independent atom model (IAM). The experimental results have been compared with results from a multipolar refinement carried out using theoretical structure factors generated from density functional theory (DFT) calculations. Very strong classical hydrogen bonds drive the cocrystallization and lend stability to the resulting cocrystal. Important conclusions have been drawn about this transition.

Leverage analysis of X-ray single crystal diffraction data from orthopyroxene and pigeonite

2002 ◽  
Vol 14 (4) ◽  
pp. 773-783 ◽  
Author(s):  
Marcello Merli ◽  
Fernando Cámara ◽  
Chiara Domeneghetti ◽  
Vittorio Tazzoli
Keyword(s):  
Single Crystal ◽  
Diffraction Data ◽  
Single Crystal Diffraction ◽  
X Ray

A synchrotron X-ray diffraction analysis of near-stoichiometric LiNbO3

2001 ◽  
Vol 216 (8) ◽  
Author(s):  
B. Etschmann ◽  
N. Ishizawa ◽  
V. Streltsov ◽  
S. Oishi
Keyword(s):  
Single Crystal ◽  
Diffraction Analysis ◽  
Diffraction Data ◽  
X Ray Diffraction ◽  
Single Crystal Diffraction ◽  
X Ray

AbstractSingle-crystal diffraction data was collected at 120 and 294 K for an approximately spherical LiNbO

Indexing of multi-particle diffraction data in a high-pressure single-crystal diffraction experiment

2013 ◽  
Vol 46 (2) ◽  
pp. 387-390 ◽  
Author(s):  
Hui Li ◽  
Xiaodong Li ◽  
Meng He ◽  
Yanchun Li ◽  
Jing Liu ◽  
...  
Keyword(s):  
Genetic Algorithm ◽  
High Pressure ◽  
Single Crystal ◽  
Single Crystals ◽  
Diffraction Data ◽  
Reciprocal Lattice ◽  
Powder Pattern ◽  
Diffraction Experiment ◽  
Crystal Data ◽  
Single Crystal Diffraction

High-pressure single-crystal diffraction experiments often suffer from the crushing of single crystals due to the application of high pressure. Consequently, only diffraction data resulting from several particles in random orientations is available, which cannot be routinely indexed by commonly used methods designed for single-crystal data. A protocol is proposed to index such diffraction data. The techniques of powder pattern indexing are first used to propose the possible lattice parameters, and then a genetic algorithm is applied to determine the orientation of the reciprocal lattice for each of the particles. This protocol has been verified experimentally.

scholarly journals Theoretical analysis of double-crystal spectrograph for high-resolution spectroscopy of laser-generated X-rays

1992 ◽  
Vol 10 (4) ◽  
pp. 841-847 ◽  
Author(s):  
O. Renner ◽  
M. Kopecký
Keyword(s):  
High Resolution ◽  
Single Crystal ◽  
Resolving Power ◽  
High Resolution Spectroscopy ◽  
High Dispersion ◽  
X Rays ◽  
Plasma Spectroscopy ◽  
Single Crystal Diffraction ◽  
Double Crystal ◽  
Quantitative Characteristics

Vertical dispersion variant of the double-crystal spectrograph is analyzed and its basic quantitative characteristics (luminosity, resolving power) are computed using ray tracing code. It is shown that geometric apparatus smearing is minimized due to high dispersion and spectral resolution may considerably exceed the single-crystal diffraction limit. Performing high-resolution spectral work, the efficiency of the double-crystal apparatus exceeds that of the flat single-crystal spectrograph. The usefulness of this method in laser plasma spectroscopy is demonstrated analyzing the detection of phosphorus He-like resonance line and its satellites.

Sign in / Sign up

Export Citation Format

Share Document