Seifertite
SiO2
third-order Birch-Murnaghan · Original · 2019
Why this differs from similar rows?
Table 1 'This study' model with q fixed to 1 (same as Table 2 Model 2); sibling rows in Table 2 use different fixed q values (0.8, 1.2), changing the fitted K_T0.
V₀
92.3
ų
Unit cell
K₀
290
GPa
Isothermal
K′
4
dimensionless
Volume (V₀)
| Value | Unit | Basis | Z |
|---|---|---|---|
| 92.3 | 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 |
|---|---|
| SiO2 | 1 |
Formula: SiO2
Conditions & method
- Tref
- 300 K
- Pref
- —
- Structure
- alpha-PbO2-type (seifertite)
- Method
- experiment (XRD / DAC / multianvil compression)synchrotron XRD in laser-heated diamond anvil cell
- Sample
- This study, Table 1 (q = 1 fixed, Model 2)
Source
- Paper
- High Pressure‐Temperature Study on the Thermal Equations of State of Seifertite…
- Authors
- Ningyu Sun; Weigang Shi; Zhu Mao; Cijin Zhou; Vitali B. Prakapenka
- DOI
- 10.1029/2019jb017853
- Year
- 2019
- Journal
- Journal of Geophysical Research Solid Earth
- Origin
- Original (measured or fitted in the source paper)
Evidence from the paper
Seifertite has a greater K_T0 = 290(10) GPa (K_T' = 4 fixed) than CaCl2-type SiO2. Other thermoelastic parameters of seifertite are V0 = 92.3(5) Å3, γ0 = 1.6(2), q = 1 (fixed), and θ_D0 = 1600(200) K. (Table 1: This study 290 (10), 4 (fixed), 92.3 (5), 1600 (200), 1.6 (2), 1 (fixed))
Additional notes
theta D0 K
1600 (200)
gamma 0
1.6 (2)
q
1 (fixed)
pressure scale
NaCl thermal EoS (Fei et al., 2007)
P T range
55–147 GPa, up to 3500 K