Post-perovskite
MgGeO3
Birch-Murnaghan (order unspecified) · Original · 2005
V₀
179.7
ų
Unit cell
K₀
203
GPa
Unknown
K′
4.400
dimensionless
Volume (V₀)
| Value | Unit | Basis | Z |
|---|---|---|---|
| 179.7 | ų | Unit cell | — |
Reported value and unit are preserved as extracted. Z (formula units per cell) is not stored yet, so molar ↔ ų/f.u. conversion is not applied automatically.
Composition
| Oxide | Molar |
|---|---|
| MgO | 1 |
| GeO2 | 1 |
Formula: MgGeO3
Conditions & method
- Tref
- —
- Pref
- —
- Structure
- post-perovskite (CaIrO3-type, Cmcm)
- Method
- experiment (XRD / DAC / multianvil compression)laser-heated diamond anvil cell, angle-dispersive X-ray diffraction (13-ID-D, Advanced Photon Source)
- Sample
- MgGeO3-ppv synthesized from MgGeO3 orthopyroxene at 86 GPa, ~1600 K
Source
- Paper
- Shock-induced superheating-melting and geophysical Implications
- Authors
- Shuanghua Luo
- DOI
- 10.1107/s0108767305096972
- Year
- 2005
- Journal
- Acta Crystallographica Section A Foundations of Crystallography
- Origin
- Original (measured or fitted in the source paper)
Evidence from the paper
EoS data (bulk modulus, its pressure derivative, and room pressure unit cell volume) were obtained using Birch-Murnaghan EoS to be 203(6) GPa, 4.4, 179.7(9) A3 for MgGeO3-ppv
Additional notes
note
Kp quoted without uncertainty (4.4), possibly fixed during fit; germanate analog of silicate post-perovskite. Rietveld refinement performed with GSAS/EXPGUI; change in compression mechanism at ~45 GPa.