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Updated: Jul 11, 2026
10:12
Synchrotron X-ray Microdiffraction and Fluorescence Imaging of Mineral and Rock Samples
Published on: June 19, 2018
Montmorillonite: electron diffraction from two-dimensional single crystals
Science (New York, N.Y.)
|May 26, 1972
Summary
Electron diffraction patterns challenge the accepted structure of sodium-titanium-montmorillonites. A triclinic model may better explain the observed symmetry in these clay minerals.
Area of Science:
- Mineralogy
- Crystallography
- Materials Science
Background:
- Montmorillonites are clay minerals with layered structures.
- The accepted structure of sodium-titanium-montmorillonites assumes specific symmetry planes.
- Electron diffraction is a key technique for determining crystal structures.
Purpose of the Study:
- To investigate the crystal structure of Wyoming and Camp Berteaux sodium-titanium-montmorillonites.
- To evaluate the validity of the accepted structural model based on experimental data.
Main Methods:
- Selected area electron diffraction (SAED) was performed on isolated monocrystalline particles.
- Analysis of diffraction patterns to determine symmetry elements.
Main Results:
- SAED patterns from both Wyoming and Camp Berteaux sodium-titanium-montmorillonites did not exhibit the expected mirror plane symmetry.
- The observed diffraction data are inconsistent with the currently accepted structural model.
Conclusions:
- The accepted structural model for sodium-titanium-montmorillonites may be inaccurate.
- A triclinic crystal system should be considered as an alternative model to explain the observed diffraction patterns.
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