1. Shock-driven amorphization and melt in Fe$_2$O$_3$
- Author
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Crépisson, Céline, Amouretti, Alexis, Harmand, Marion, Sanloup, Chrystèle, Heighway, Patrick, Azadi, Sam, McGonegle, David, Campbell, Thomas, Chin, David Alexander, Smith, Ethan, Hansen, Linda, Forte, Alessandro, Gawne, Thomas, Lee, Hae Ja, Nagler, Bob, Shi, YuanFeng, Fiquet, Guillaume, Guyot, François, Makita, Mikako, Benuzzi-Mounaix, Alessandra, Vinci, Tommaso, Miyanishi, Kohei, Ozaki, Norimasa, Pikuz, Tatiana, Nakamura, Hirotaka, Sueda, Keiichi, Yabuuchi, Toshinori, Yabashi, Makina, Wark, Justin S., Polsin, Danae N., and Vinko, Sam M.
- Subjects
Condensed Matter - Materials Science ,High Energy Physics - Experiment - Abstract
We present measurements on Fe$_2$O$_3$ amorphization and melt under laser-driven shock compression up to 209(10) GPa via time-resolved in situ x-ray diffraction. At 122(3) GPa, a diffuse signal is observed indicating the presence of a non-crystalline phase. Structure factors have been extracted up to 182(6) GPa showing the presence of two well-defined peaks. A rapid change in the intensity ratio of the two peaks is identified between 145(10) and 151(10) GPa, indicative of a phase change. Present DFT+$U$ calculations of temperatures along Fe$_2$O$_3$ Hugoniot are in agreement with SESAME 7440 and indicate relatively low temperatures, below 2000 K, up to 150 GPa. The non-crystalline diffuse scattering is thus consistent with the - as yet unreported - shock amorphization of Fe$_2$O$_3$ between 122(3) and 145(10) GPa, followed by an amorphous-to-liquid transition above 151(10) GPa. Upon release, a non-crystalline phase is observed alongside crystalline $\alpha$-Fe$_2$O$_3$. The extracted structure factor and pair distribution function of this release phase resemble those reported for Fe$_2$O$_3$ melt at ambient pressure., Comment: 11 pages, 4 figures, under review
- Published
- 2024