Bridgmanite
FeMg0.5Si0.5O3
second-order Birch-Murnaghan · Original · 2023
V₀
181.2
ų
Unit cell
K₀
199
GPa
Isothermal
K′
4
dimensionless
Volume (V₀)
| Value | Unit | Basis | Z |
|---|---|---|---|
| 181.2 | 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 | 0.5 |
| Fe2O3 | 0.5 |
| SiO2 | 0.5 |
Formula: FeMg0.5Si0.5O3
Conditions & method
- Tref
- —
- Pref
- —
- Structure
- perovskite (unspecified)
- Method
- experiment (XRD / DAC / multianvil compression)single-crystal X-ray diffraction in diamond anvil cell (ID15B, ESRF)
- Sample
- single crystal synthesized in Kawai-type multi-anvil press
Source
- Paper
- Crystal chemistry and compressibility of Fe0.5Mg0.5Al0.5Si0.5O3 and FeMg0.5Si0.…
- Authors
- Iuliia Koemets; Biao Wang; Egor Koemets; Takayuki Ishii; Zhaodong Liu; Catherine McCammon; Artem Chanyshev; Tomo Katsura; Michael Hanfland; Alexander Chumakov; Leonid Dubrovinsky
- DOI
- 10.3389/fchem.2023.1258389
- Year
- 2023
- Journal
- Frontiers in Chemistry
- Origin
- Original (measured or fitted in the source paper)
Evidence from the paper
FeMg0.5Si0.5O3 is stable in the trigonal corundum derivative structure below 12 ± 2 GPa. Above 12 ± 2 GPa, it adopts a monoclinic double-perovskite structure. The BM2–EoS fitting of data between 12 and 40 GPa gives K0 = 199 ± 6 GPa and V0 = 181.2 ± 0.5 Å3.
Additional notes
Kp note
K′ = 4 is implied by the second-order Birch–Murnaghan EoS truncation; not explicitly stated as a number in the text
softening note
Above 40 GPa, elastic softening related to spin transition of Fe3+ located in the B-sites of perovskite; fit restricted to 12–40 GPa