Superhydrous phase B

Mg8.99Si2.77Al0.54O18H5.25

finite strain (unspecified form) · Original · 2024

V₀

621.69

Å³

Unit cell

K₀

150

GPa

Adiabatic

K′

4.200

dimensionless

Volume (V₀)

Value	Unit	Basis	Z
621.69	Å³	Unit cell	—

Reported value and unit are preserved as extracted. Z (formula units per cell) is not stored yet, so molar ↔ Å³/f.u. conversion is not applied automatically.

Composition

Oxide	Molar
MgO	8.99
Al2O3	0.27
SiO2	2.77
H2O	2.625

Formula: Mg8.99Si2.77Al0.54O18H5.25

Conditions & method

T_ref: 300 K
P_ref: —
Structure: other / unspecified
Method: experiment (Brillouin / ultrasonic / elasticity)
ultrasonic interferometry (VP, VS) + synchrotron X-ray diffraction density in Kawai-type multi-anvil apparatus
Sample: S3359 (polycrystalline), high P-T global fit

Source

Paper: Effect of Al‐Incorporation on the Sound Velocities of Superhydrous Phase B at H…
Authors: Chaowen Xu; Steeve Gréaux; Ying Chun Li; Fengxia Sun; Jing Gao; Fei Qin; Toru Inoue
DOI: 10.1029/2023gl107818
Year: 2024
Journal: Geophysical Research Letters
Origin: Original (measured or fitted in the source paper)

Evidence from the paper

Table 1 (Finite strain EoS, P-scale free): S3359, 14.8–22.1 GPa/300–1300 K, V0 = 621.69a, 150 (7), 4.2 (6), ∂KS/∂T = −0.019 (2), G0 = 93 (4), ∂G/∂P = 2.0 (2), ∂G/∂T = −0.022 (2), α0 = 4.3a. 'Because of limited data, we could not constrain the room T moduli of S3359 and therefore used those of S3358 as the initial assumption for the high-T fitting of S3359.'

Additional notes

dKS dT GPa per K

−0.019 (2)

G0 GPa

93 (4)

dG dP

2.0 (2)

dG dT GPa per K

−0.022 (2)

alpha0 1e-5 per K

4.3 (fixed)

P T conditions

14.8–22.1 GPa / 300–1300 K

V0 fixed in fit

True

note

Room-T moduli of S3358 used as initial assumption for S3359 fit