Analysis of pulsed-neutron powder diffraction patterns of the icosahedral quasicrystals Pd3Siu and AlCuLiMg (three alloys) as twinned cubic crystals with large units.

The modelling and/or describing of texture (i.e. preferred crystallographic orientation (PO)) is of critical importance in powder diffraction analysis - for structural study and phase composition. In the present study, the GSAS Rietveld refinement with generalized spherical harmonic (GSH) was used for describing isostatically-pressed molybdite powders neutron powder diffraction data collected in the ILL D1A instrument. The results showed that for texture in a single ND data of molybdite the reasonable crystal structure parameters may be obtained when applying corrections to intensities using the GSH description. Furthermore, the WIMV method was used to extract the texture description directly from a simultaneous refinement with 1368 whole neutron diffraction patterns taken from the sample held in a variety of orientations in the ILL D1B texture goniometer. The results provided a quantitative description of the texture refined simultaneously with the crystal structure. Finally, the (002) molybdite pole-figures were measured using the GKSS TEX2 texture goniometer. The results showed that neutron diffraction is an excellent tool to investigate the texture in molybdite.

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Pulsed-neutron powder-diffraction study of lead sulfide and deuterium ions in zeolite Y

The Journal of Physical Chemistry ◽

10.1021/j100131a048 ◽

1993 ◽

Vol 97 (29) ◽

pp. 7719-7723 ◽

Cited By ~ 48

Author(s):

Tao Sun ◽

Karl Seff

Keyword(s):

Diffraction Study ◽

Powder Diffraction ◽

Lead Sulfide ◽

Zeolite Y ◽

Neutron Powder Diffraction ◽

Pulsed Neutron

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Applications of Pulsed Neutron Powder Diffraction to Actinide Elements

Advances in X-Ray Analysis ◽

10.1007/978-1-4613-1035-8_42 ◽

1988 ◽

pp. 385-393

Author(s):

A. C. Lawson ◽

B. Cort ◽

C. E. Olsen ◽

J. W. Richardson ◽

M. H. Mueller ◽

...

Keyword(s):

Powder Diffraction ◽

Neutron Powder Diffraction ◽

Pulsed Neutron ◽

Actinide Elements

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Measurement of Atomic Elastic Constants by Pulsed Neutron Powder Diffraction

Advances in X-ray Analysis ◽

10.1154/s0376030800019212 ◽

1992 ◽

Vol 36 ◽

pp. 577-583

Author(s):

A. C. Lawson ◽

G. H. Kwei ◽

J. A. Goldstone ◽

B. Cort ◽

R. I. Sheldon ◽

...

Keyword(s):

High Temperature ◽

Neutron Diffraction ◽

Rietveld Refinement ◽

Powder Diffraction ◽

Elastic Constants ◽

Diffraction Data ◽

High Temperature Superconductors ◽

Neutron Powder Diffraction ◽

Neutron Diffraction Data ◽

Pulsed Neutron

AbstractWe have developed a technique for determining the atomic elastic constants from measurements of the Debye-Waller factors. The Debye-Waller factors are obtained by Rietveld refinement of time-of-flight neutron diffraction data and interpreted in terms of an atomic Debye-Waller temperature. The method is applicable to powders and to materials that must be encapsulated for safety or environmental reasons. We will illustrate our technique with applications to actinide metals, to metallic hydrides and to high-temperature superconductors.

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High-temperature structural evolution of hexagonal multiferroic YMnO3and YbMnO3

Journal of Applied Crystallography ◽

10.1107/s0021889807025101 ◽

2007 ◽

Vol 40 (4) ◽

pp. 730-734 ◽

Cited By ~ 40

Author(s):

Il-Kyoung Jeong ◽

N. Hur ◽

Th. Proffen

Keyword(s):

Phase Transition ◽

High Temperature ◽

Powder Diffraction ◽

Structural Parameters ◽

Structural Evolution ◽

Neutron Powder Diffraction ◽

Temperature Behaviour ◽

Rietveld Refinements ◽

Polar Structure ◽

Diffraction Patterns

Neutron powder diffraction studies on the structural evolution of hexagonal multiferroic YMnO3and YbMnO3from 1000 K to 1400 K, and from 1000 K to 1350 K, respectively, are presented. The temperature evolution of diffraction patterns suggests that YMnO3undergoes a phase transition to a non-polar structure above 1200 K, while YbMnO3remains ferroelectric up to 1350 K. Detailed structural parameters were obtained as a function of temperature from Rietveld refinements. Based on this result, the distinct differences in temperature behaviour between YMnO3and YbMnO3, and the origin of the ferroelectricity in these hexagonal multiferroics are discussed.

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