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Updated: May 10, 2026
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Bulk and Thin Film Synthesis of Compositionally Variant Entropy-stabilized Oxides
Published on: May 29, 2018
Lattice dynamics of coesite
Björn Wehinger1, Alexeï Bosak, Aleksandr Chumakov
1European Synchrotron Radiation Facility, BP 220 F-38043 Grenoble Cedex, France. wehinger@esrf.fr
Summary
Lattice dynamics of coesite were investigated using X-ray scattering and computational methods. This study reveals key vibrational properties and compares them to alpha-quartz, offering insights into SiO2 polymorph behavior.
Area of Science:
- Solid-state physics
- Materials science
- Geophysics
Background:
- Coesite is a high-pressure polymorph of silica (SiO2).
- Understanding lattice dynamics is crucial for material properties like elasticity and stability.
- Previous studies on coesite's vibrational properties are limited.
Purpose of the Study:
- To comprehensively study the lattice dynamics of coesite.
- To determine elastic properties, stability, and metastability.
- To investigate vibrational eigenvectors, mode character, and density of states.
Main Methods:
- Diffuse X-ray scattering (DXS)
- Inelastic X-ray scattering (IXS)
- Ab initio lattice dynamics calculations
Main Results:
- Experimental data validated ab initio calculations.
- Detailed analysis of reciprocal space scattering and vibrational spectra.
- Identified a critical point at the zone boundary strongly influencing low-energy density of states.
- Reported dispersion relations and density of vibrational states.
Conclusions:
- The combined experimental and computational approach provides a full harmonic description of coesite's lattice dynamics.
- Coesite exhibits distinct low-energy vibrational properties compared to alpha-quartz.
- Findings contribute to understanding the behavior of SiO2 polymorphs under various conditions.
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