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Confocal Imaging of Confined Quiescent and Flowing Colloid-polymer Mixtures
Published on: May 20, 2014
Crystallography of ordered colloids using optical microscopy. 2. Divergent-beam technique.
Richard B Rogers1, K Peter D Lagerlöf
1Department of Materials Science and Engineering, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106, USA. richard.b.rogers@nasa.gov
Applied Optics
|April 12, 2008
Summary
A new divergent-beam technique accurately extracts crystallographic data from colloidal crystals. This method offers an easier alternative to parallel-beam approaches for materials analysis.
Area of Science:
- Materials Science
- Crystallography
- Colloid Science
Background:
- Extracting quantitative crystallographic data from randomly oriented colloidal crystals presents significant challenges.
- Existing methods, like the parallel-beam approach, have limitations in ease of implementation and robustness.
Purpose of the Study:
- To develop and validate a novel divergent-beam technique for extracting crystallographic data from colloidal crystals.
- To compare the efficacy and limitations of the divergent-beam approach against existing methods.
Main Methods:
- Utilized a divergent-beam X-ray diffraction technique.
- Applied the method to analyze colloidal crystals composed of poly-(methyl methacrylate) spheres in index-matching solvents.
- Tested on diverse experimental images of colloidal crystal structures.
Main Results:
- Successfully extracted complete sets of reciprocal lattice basis vectors in most cases.
- Achieved high accuracy, with lattice parameters precise to approximately 1% and orientation to within 2 degrees.
- Identified limitations in robustness for specific crystal packing, such as hexagonal close-packed structures.
Conclusions:
- The divergent-beam technique provides an accessible and accurate method for crystallographic analysis of colloidal crystals.
- It complements the parallel-beam approach, enabling comprehensive data extraction from various colloidal crystal systems.
- This advancement facilitates quantitative crystallographic data acquisition using conventional optical microscopy.
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