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Updated: May 2, 2026
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Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
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Structural evolution and medium range order in permanently densified vitreous SiO2.
M Zanatta1, G Baldi2, R S Brusa3
1Dipartimento di Fisica, Università di Perugia, I-06123 Perugia, Italy.
Physical Review Letters
|March 4, 2014
Summary
Densification of silica glass (SiO2) significantly shrinks interstitial void spaces, impacting its structure. This study reveals voids linearly decrease in volume with increasing density, suggesting a porous medium behavior.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Solid State Chemistry
Background:
- Silica glass (SiO2) exhibits complex structural properties.
- Understanding the relationship between density and microstructure is crucial for materials design.
Purpose of the Study:
- To quantify the impact of densification on interstitial void spaces in SiO2 glass.
- To investigate how structural changes affect the properties of densified silica glass.
Main Methods:
- Positron annihilation lifetime spectroscopy (PALS) to measure void size.
- X-ray diffraction (XRD) to analyze short-range order.
Main Results:
- Densification linearly reduces interstitial void volume by nearly an order of magnitude.
- Short-range order, based on SiO4 tetrahedra, remains largely unchanged.
- Void volume variation dominates compressibility and medium-range order up to quartz-like densities.
Conclusions:
- Densified SiO2 glasses can be described as porous media.
- Void space is the primary factor governing the mechanical properties of densified silica glass.
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