perovskite (CaIrO3 analogue of MgSiO3 perovskite)

CaIrO3

third-order Birch-Murnaghan · Original · 2007

V₀

229.463

Å³

Unit cell

K₀

198

GPa

Isothermal

K′

1.200

dimensionless

Volume (V₀)

Value	Unit	Basis	Z
229.463	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

CaIrO3

Conditions & method

T_ref: —
P_ref: 0.000 GPa
Structure: orthorhombic perovskite (Pbnm/Pnma)
Method: experiment (XRD / DAC / multianvil compression)
high-pressure single-crystal X-ray diffraction in diamond anvil cell (compression to ~7.8 GPa, methanol:ethanol medium, ruby pressure standard)
Sample: single crystal (100×70×60 μm) synthesized at 1525 °C and 2.5 GPa

Source

Paper: Equations of state of CaIrO3 perovskite and post-perovskite phases
Authors: Tiziana Boffa Ballaran; Reidar G. Trønnes; D. J. Frost
DOI: 10.2138/am.2007.2715
Year: 2007
Journal: American Mineralogist
Origin: Original (measured or fitted in the source paper)

Evidence from the paper

A third-order Birch Murnaghan equation of state has been used to fit the measured P-V data with the following refined parameters: V0 = 229.463(8) Å3, K0 = 198(3) GPa, K' = 1.2(8) ... for CaIrO3 perovskite ... Table 2: V0 (Å3) 229.463(8); K0 (GPa) 198(3); K' 1.2(8). Table 1 ambient row: 0.00010(1) GPa, V = 229.463(8) Å3.

Additional notes

axial BM3 parameters

{
  "a0_A": "5.3477(1)",
  "K0_a_GPa": "146(2)",
  "Kp_a": "-1.0(5)",
  "beta0a_GPa-1": "0.00228",
  "b0_A": "5.5919(1)",
  "K0_b_GPa": "322(7)",
  "Kp_b": "26(3)",
  "beta0b_GPa-1": "0.00104",
  "c0_A": "7.6735(2)",
  "K0_c_GPa": "187(3)",
  "Kp_c": "1.2(8)",
  "beta0c_GPa-1": "0.00178"
}

F-f fit

FE = 198(3) - 825(244)fE

fitting software

Eosfit52 program (Angel 2002)

note

CaIrO3 perovskite is a low-pressure structural analogue for MgSiO3 perovskite in the Earth's lower mantle; decompression data point at 5.26 GPa excluded from fit