ε-FeOOH
FeOOH
third-order Birch-Murnaghan · Original · 2017
Why this differs from similar rows?
BM3 fit to the high-pressure H-bond-symmetrized (HC) structure, 30-140 GPa; sibling entry is the low-pressure HOC structure over 0-20 GPa; symmetrization raised K0, lowered K'.
V₀
58.62
ų
Unit cell
K₀
223
GPa
Isothermal
K′
4.070
dimensionless
Volume (V₀)
| Value | Unit | Basis | Z |
|---|---|---|---|
| 58.62 | 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 |
|---|---|
| Fe2O3 | 0.5 |
| H2O | 0.5 |
Formula: FeOOH
Conditions & method
- Tref
- —
- Pref
- —
- Structure
- other / unspecified
- Method
- DFT+U / DFT+DMFTfirst-principles DFT (GGA+U), static 0 K calculations
- Sample
- DFT GGA+U (self-consistent U) optimized structures, unit cell, 30–140 GPa
Source
- Paper
- Elasticity of ε‐FeOOH: Seismic implications for Earth's lower mantle
- Authors
- Elizabeth C. Thompson; A. J. Campbell; Jun Tsuchiya
- DOI
- 10.1002/2017jb014168
- Year
- 2017
- Journal
- Journal of Geophysical Research Solid Earth
- Origin
- Original (measured or fitted in the source paper)
Evidence from the paper
Table 2. Birch-Murnaghan Equation of State Parameters ... High-Pressure Hydrogen Bond Symmetrized Structure (HC; 30–140 GPa) for Self-Consistent U-Value Calculations: V0 (Å3) 58.62(5); K0 (GPa) 223(2); K'0 4.07(3). 'The reference volume (V0) was treated as a free parameter in the equation of state fitting.'
Additional notes
pressure range
30–140 GPa
notes
Hydrogen bond symmetrization led to a ~19% increase in K0 and a ~22% reduction of K'0