| About this Abstract |
| Meeting |
Materials Science & Technology 2020
|
| Symposium
|
Glasses, Optical Materials, and their Functional Applications: Current Issues in Science & Technology
|
| Presentation Title |
Glasses beyond Megabar Pressures |
| Author(s) |
Sung Keun Lee |
| On-Site Speaker (Planned) |
Sung Keun Lee |
| Abstract Scope |
We provide an overview of the recent experimental progress and insights by X-ray Raman scattering (XRS) into structures of oxide glasses under compression above megabar pressures. A densification of amorphous oxides under extreme compression is dominated by reorganization of oxygen during compression. XRS spectra for SiO2 glass up to 1.6 Mbar reveal the evolution of heavily contracted oxygen environments characterized by a decrease in average O..O distance and the emergence of quadruply coordinated oxygen. Our results also yield the predictive relationship between the density and partial density of state of oxides above megabar pressures. The extreme densification paths with densified oxygen in amorphous oxides shed light upon the possible existence of stable melts in the planetary interiors [Lee.et al., Phys. Rev. Lett., 123 235701 (2019); PNAS 115, 5855 (2018); Kim et al. Geophy. Res. Lett., 46 13756 (2019)]. |