Phase D
Mg0.89Fe0.11Al0.37Si1.55H2.65O6
Birch-Murnaghan (order unspecified) · Original · 2016
V₀
85.711
ų
Unit cell
K₀
—
K′
—
dimensionless
Volume (V₀)
| Value | Unit | Basis | Z |
|---|---|---|---|
| 85.711 | 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 | 0.89 |
| FeO | 0.11 |
| Al2O3 | 0.185 |
| SiO2 | 1.55 |
| H2O | 1.325 |
Formula: Mg0.89Fe0.11Al0.37Si1.55H2.65O6
Conditions & method
- Tref
- —
- Pref
- —
- Structure
- other / unspecified
- Method
- experiment (XRD / DAC / multianvil compression)in situ high-pressure single-crystal X-ray diffraction in diamond anvil cell (He pressure medium, Pt pressure calibrant)
- Sample
- single crystal 5K2209 (FeAl-bearing phase D)
Source
- Paper
- Two‐stage spin transition of iron in FeAl‐bearing phase D at lower mantle
- Authors
- Xiang Wu; Ye Wu; Jung‐Fu Lin; Jin Liu; Zhu Mao; Xinzhuan Guo; Takashi Yoshino; Catherine McCammon; Vitali B. Prakapenka; Yuming Xiao
- DOI
- 10.1002/2016jb013209
- Year
- 2016
- Journal
- Journal of Geophysical Research Solid Earth
- Origin
- Original (measured or fitted in the source paper)
Evidence from the paper
The crystal structure at ambient conditions was determined to be hexagonal phase (P3m and Z = 1) with lattice constants of a = 4.7855(1) Å, c = 4.3212(4) Å, and V = 85.711(7) ų for FeAl-bearing phase D ... We used the Birch-Murnaghan equation of state to describe the P-V relationship: 0.0001–37 GPa for Fe2+(HS)Fe3+(HS) state (denoted HS-phase D), 41–64 GPa for Fe2+(LS)Fe3+(HS) state (Mixed-spin phase D), and 68–110 GPa for Fe2+(LS)Fe3+(LS) state (denoted LS-phase D), where all parameters are summarized in Table S4.
Additional notes
spin state
high-spin Fe2+ and Fe3+ (HS-phase D) for the 0.0001–37 GPa fit; mixed-spin (41–64 GPa) and low-spin (68–110 GPa) fits also performed
lattice constants
a = 4.7855(1) Å, c = 4.3212(4) Å
water content
~13.3 wt % (estimated from mass and charge balance from EMPA)
Fe3+ over total Fe
0.40(5)
note
Fitted K0 and K' values are summarized in Table S4 (supporting information), not reproduced in the main text; volume discontinuities of ~1.7% at 37–41 GPa and ~2.0% at 64–68 GPa associated with two-stage spin transition