Shock-wave compression of vitreous and rutile-type GeO_2: A comparative study
- Creators
- Jackson, Ian
- Ahrens, Thomas J.
Abstract
The dynamic compression of both vitreous and rutile-type GeO_2 has been studied throughout the pressure range 0–160 GPa (1.6 Mbar). At sufficiently high pressures (respectively >35 GPa and >70 GPa) both materials attain densities greater than those expected for the rutile phase at the same pressure. These results may be explained in terms of transformation of both vitreous and rutile-type GeO_2 to a common high-pressure phase or state with a zero-pressure density ∼5% greater than that of the rutile polymorph. The vastly different thermal regimes associated with the two Hugoniots allow important deductions to be made concerning the elastic and thermodynamic properties of shocked germanium dioxide. In particular, an effective Grüneisen parameter of 1.24 ± 0.1 is required at a density of 7.4 g/cm^3. Inconsistency between this value and those calculated from the Vashchenko-Zubarev model suggests that the latter may not provide an adequate description of the thermal properties of close-packed germanates and silicates.
Additional Information
© 1979 Elsevier Scientific Publishing Company. Received January 25, 1979; revised and accepted May 2, 1979. We thank C.S. Sahagian of the Solid State Sciences Laboratory, Hanscom Air Force Base, Massachusetts and J.S. White of the Division of Mineralogy, National Museum of Natural History, Smithsonian Institution, Washington for making available the crystals of rutile-type GeO2 without which this work would not have been possible. H. Richeson, E. Gelle and R. Smith are thanked for their assistance in conducting the experiments. Much fruitful discussion with R. Jeanloz, L. Liu, A.E. Ringwood, L. Thomsen and D.J. Weidner is also acknowledged. The manuscript was improved a result of thoughtful comments by an anonymous reviewer. Financial support was provided by the U.S. National Science Foundation (Grant EAR-75-15006A01).Additional details
- Alternative title
- Shock-wave compression of vitreous and rutile-type GeO2: A comparative study
- Eprint ID
- 53081
- DOI
- 10.1016/0031-9201(79)90108-0
- Resolver ID
- CaltechAUTHORS:20141222-101655990
- EAR 75-15006A01
- NSF
- Created
-
2014-12-22Created from EPrint's datestamp field
- Updated
-
2021-11-10Created from EPrint's last_modified field