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Preferred orientation and its effects on intensity-correlation measurements.
Jack Binns1, Connie Darmanin2, Cameron M Kewish3,4
1School of Science, RMIT University, Melbourne, Victoria 3000, Australia.
Iucrj
|April 4, 2022
Summary
Intensity-correlation measurements reveal nanostructural details. Preferred orientation effects in materials can dominate these signals, especially with many crystalline domains, impacting analysis.
Area of Science:
- Materials Science
- Crystallography
- Scattering Techniques
Background:
- Intensity-correlation methods provide nanostructural insights beyond traditional pair-correlation.
- Preferred orientation (texture) is typically analyzed separately and can complicate correlation data.
Purpose of the Study:
- Develop theory connecting preferred orientation to intensity-correlation techniques.
- Investigate the influence of preferred orientation on pair-angle distribution function (PADF) analysis.
- Demonstrate experimental cases of orientation-dominant and nanostructure-dominant signals.
Main Methods:
- Theoretical development linking texture analysis to intensity-correlation.
- Application of pair-angle distribution function (PADF) analysis.
- Experimental measurements on materials with varying degrees of preferred orientation.
Main Results:
- Preferred orientation effects scale with the number of crystalline domains.
- Orientation signals can surpass nanostructural signals in samples with many domains.
- Even minor orientation deviations yield strong angular correlation signals with sufficient domains.
Conclusions:
- Preferred orientation is a significant factor in intensity-correlation experiments, not just an error source.
- PADF analysis can reveal both nanostructural and microstructural (orientation) information.
- Understanding and accounting for preferred orientation is crucial for accurate correlation analysis.
Keywords:
X-ray free-electron lasersXFELscorrelated fluctuationscrystalline domainsdynamical studiesfluctuation scatteringintensity correlationspair-angle distribution functionspreferred orientationMore Related Videos
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