Shock-Induced Phase Transitions in Rutile Single Crystal
- Murli H. Manghnani and
- Yasuhiko Syono
Published Online: 21 MAR 2013
Copyright © 1987 by Terra Scientific Publishing Company (TERRAPUB), Tokyo.
High-Pressure Research in Mineral Physics: A Volume in Honor of Syun-iti Akimoto
How to Cite
Syono, Y., Kusaba, K., Kikuchi, M., Fukuoka, K. and Goto, T. (1987) Shock-Induced Phase Transitions in Rutile Single Crystal, in High-Pressure Research in Mineral Physics: A Volume in Honor of Syun-iti Akimoto (eds M. H. Manghnani and Y. Syono), American Geophysical Union, Washington, D. C.. doi: 10.1029/GM039p0385
- Published Online: 21 MAR 2013
- Published Print: 1 JAN 1987
Print ISBN: 9780875900667
Online ISBN: 9781118664124
- Mineralogy and Crystal Chemistry;
- Phase transformations;
- High Pressure-High Temperature Research
Shock compression experiments on single crystal rutile, TiO2, were carried to pressure of 123 GPa. Flyer plates, gun-launched to speeds of 4.4 km/s, were used as impactors to induce shock waves. Shock and free surface velocities were measured using streak photography. Pressures and volumes were calculated from the measured shock velocities and particle velocities using conservation relations. Hugoniot elastic limits (HEL) were measured to be 6.2, 6.8, and 7.0 GPa for shock loading along the , , and  directions, respectively. The shock compression data for the (lower pressure) rutile phase was in agreement with static compression, as well as ultrasonic, measurements. Phase transition pressures observed depended strongly on the shock propagation direction, i.e., 13.7±0.3, 16.9±1.8, and 33.8±0.3 GPa for , , and  respectively. A new high-pressure phase (HPP-I), which showed a different pressure-volume trend from that previously reported by McQueen et al. (1967) and Altshuler et al. (1973) (HPP-II), was found between 70 and 100 GPa. The estimated zero-pressure density of HPP-I was 5.00 g/cm3, 17.6 percent denser than the rutile form. This volume change suggests the phase transition from rutile to fluorite-like phase, consistent with the model, which could explain the observed anisotropy in phase transition pressures. Release adiabat measurements clearly distinguished HPP-II from HPP-I. An extremely high density of HPP-II can be ascribed to the change in bond nature itself at high pressures.