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Phase D

20.7 wt% MgO, 44.5 wt% SiO2, 18.8 wt% Al2O3, ~16.0 wt% H2O (EDS)

Birch-Murnaghan (order unspecified) · Original · 2020

Why this differs from similar rows?

Main-text fit: V0 fixed at 86.71 A^3, K_T0 and K_T0' both fitted freely from the room-T P-V-T data, yielding K_T0=143(4), K'=5.8(6); sibling Table 1 rows instead fix K0 or fit it differently.

V₀
86.71
ų
Unit cell
K₀
143
GPa
Isothermal
K′
5.800
dimensionless

Volume (V₀)

Value Unit Basis Z
86.71 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

OxideMolar
MgO0.8968
Al2O30.322
SiO21.2932
H2O1.5508

Formula: 20.7 wt% MgO, 44.5 wt% SiO2, 18.8 wt% Al2O3, ~16.0 wt% H2O (EDS)

Conditions & method

Tref
300 K
Pref
Structure
other / unspecified
Method
experiment (Brillouin / ultrasonic / elasticity)
in situ synchrotron X-ray diffraction with ultrasonic measurements in Kawai-type multianvil apparatus (Gold P-scale, Tsuchiya, 2003)
Sample
polycrystalline Al-bearing phase D synthesized at 24 GPa and 1373 K

Source

Paper
Sound Velocities of Al‐Bearing Phase D up to 22 GPa and 1300 K
Authors
Chaowen Xu; Steeve Gréaux; Toru Inoue; Masamichi Noda; Wei Sun; H. Kuwahara; Yuji Higo
DOI
10.1029/2020gl088877
Year
2020
Journal
Geophysical Research Letters
Origin
Original (measured or fitted in the source paper)

Evidence from the paper

we chose to fix the zero-pressure unit cell volume value to V0 = 86.71 Å3 ... The fitting yielded: K_T0 = 143 (4) GPa, K_T0' = 5.8 (6), (∂K_T0/∂T)_P = -0.027 (12) GPa/K^-1, and α0 = 3.8 (4) × 10^-5 K^-1

Additional notes

P T range
up to 21.9 GPa and 1300 K
dKT dT
-0.027 (12) GPa/K^-1
alpha0
3.8 (4) × 10^-5 K^-1