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The glass transition temperatures of common binary oxides, including those with low glass-forming ability, are estimated using pair distribution functions (PDFs) from ab initio molecular dynamics simulations. The computed glass transition temperatures for good glass-formers such as silica (SiO2), germania (GeO2), and boron oxide (B2O3) are in agreement with measured values. These calculations are then used to compute the glass transition temperatures of alumina (Al2O3), tantala (Ta2O5), and telluria (TeO2), which are known to exhibit low glass-forming ability. For Al2O3 and Ta2O5, we also compute the simulated caloric curve from molecular dynamics simulations using two-body empirical force fields. Finally, we discuss the possibility of extracting the glass transition temperature by measuring the thermal broadening of the PDFs from scattering measurements.
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Melting the Glass Ceiling in Physics
The words “glass ceiling” have long described the barrier preventing women and other minority populations from being promoted to top tier positions in their professions. The 1400 Degrees Initiative, which borrows its name from the typical melting temperature of glass, takes a multifaceted approach to the issue of gender equity in physics and astronomy.
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- Award ID(s):
- 1905474
- PAR ID:
- 10381050
- Editor(s):
- Simonetta Liutti
- Date Published:
- Journal Name:
- CSWP COM gazette
- Volume:
- 41
- Issue:
- 1
- ISSN:
- 2327-0098
- Page Range / eLocation ID:
- 4-4
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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