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

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.

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

A Preparation of High Resolution Standards for Electron Microscopy. Part II

1971 ◽  
Vol 29 ◽  
pp. 160-161
Author(s):  
Akira Tanaka ◽  
David F. Harling
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Carbon Black ◽  
Single Crystal ◽  
Dark Field ◽  
Graphitized Carbon Black ◽  
Graphitized Carbon ◽  
Dark Field Imaging ◽  
Crystal Films ◽  
Micro Holes

In the previous paper, the author reported on a technique for preparing vapor-deposited single crystal films as high resolution standards for electron microscopy. The present paper is intended to describe the preparation of several high resolution standards for dark field microscopy and also to mention some results obtained from these studies. Three preparations were used initially: 1.) Graphitized carbon black, 2.) Epitaxially grown particles of different metals prepared by vapor deposition, and 3.) Particles grown epitaxially on the edge of micro-holes formed in a gold single crystal film.The authors successfully obtained dark field micrographs demonstrating the 3.4Å lattice spacing of graphitized carbon black and the Au single crystal (111) lattice of 2.35Å. The latter spacing is especially suitable for dark field imaging because of its preparation, as in 3.), above. After the deposited film of Au (001) orientation is prepared at 400°C the substrate temperature is raised, resulting in the formation of many square micro-holes caused by partial evaporation of the Au film.

Detection of a point defect in a silicon single crystal by high-resolution TEM

1995 ◽  
Vol 53 ◽  
pp. 466-467
Author(s):  
M. Awaji
Keyword(s):  
High Resolution ◽  
Single Crystal ◽  
Point Defect ◽  
Point Defects ◽  
Noise Level ◽  
Dark Field ◽  
Silicon Single Crystal ◽  
High Resolution Image ◽  
Dark Field Imaging ◽  
Field Imaging

It is necessary to improve the resolution, brightness and signal-to-noise ratio(s/n) for the detection and identification of point defects in crystals. In order to observe point defects, multi-beam dark-field imaging is one of the useful methods. Though this method can improve resolution and brightness compared with dark-field imaging by diffuse scattering, the problem of s/n still exists. In order to improve the exposure time due to the low intensity of the dark-field image and the low resolution, we discuss in this paper the bright-field high-resolution image and the corresponding subtracted image with reference to a changing noise level, and examine the possibility for in-situ observation, identification and detection of the movement of a point defect produced in the early stage of damage process by high energy electron bombardment.The high-resolution image contrast of a silicon single crystal in the [10] orientation containing a triple divacancy cluster is calculated using the Cowley-Moodie dynamical theory and for a changing gaussian noise level. This divacancy model was deduced from experimental results obtained by electron spin resonance. The calculation condition was for the lMeV Berkeley ARM operated at 800KeV.

A vacuum chamber for low background diffraction experiments

1996 ◽  
Vol 211 (9) ◽  
Author(s):  
R. B. Neder ◽  
M. Burghammer ◽  
Th. Grasl ◽  
H. Schulz
Keyword(s):  
Single Crystal ◽  
Vacuum Chamber ◽  
Single Crystal Diffraction ◽  
Low Background

AbstractWe developed a small vacuum chamber for very low background single crystal diffraction experiments. The chamber has been designed for a large Eulerian cradle. The

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