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Updated: May 29, 2025
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Preparation of Macroporous Epitaxial Quartz Films on Silicon by Chemical Solution Deposition
Published on: December 21, 2015
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First-principles calculations of quartz-coesite interfaces
Tim Schaffrinna1, Victor Milman2, Björn Winkler1
1Institute of Geosciences Goethe University Frankfurt Germany.
Journal of Applied Crystallography
|February 7, 2025
Summary
Researchers investigated atomistic interface structures during the quartz to coesite transition. They identified stable atomic layers and calculated interface and strain energies, aiding experimental identification.
Area of Science:
- Geophysics
- Materials Science
- Crystallography
Background:
- The strain-induced subsolidus martensitic transition between quartz and coesite is crucial for understanding geological processes.
- Investigating atomistic interface structures is key to elucidating transformation mechanisms.
Purpose of the Study:
- To determine the atomistic interface structures during the quartz-coesite transition.
- To calculate interface and strain energies for specific crystallographic orientations.
- To simulate experimental signatures for easier identification.
Main Methods:
- Atomistic modeling using periodic boundary conditions.
- Density-functional-theory-based tight-binding (DFTB) calculations.
- Simulation of high-resolution transmission electron microscopy (HRTEM) images and electron diffraction patterns.
Main Results:
- Identified invariant atomic layers during the quartz-coesite transformation.
- Determined orientation relationships: (1011)Qz||(010)Coe and (1321)Qz||(010)Coe.
- Calculated interface energy (~660 mJ m-2) and strain energies for both orientations.
Conclusions:
- The study provides atomistic insights into the quartz-coesite phase transition.
- Calculated energies and simulated images offer valuable data for experimental validation.
- Understanding these interfaces aids in interpreting mineral transformations under pressure.
Keywords:
HRTEMhigh-resolution transmission electron microscopymartensitic transformationsquartz–coesite interfacessolid–solid interfacesstrain-induced transitionsMore Related Videos
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