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Pressure Calibration in DAC -- Challenges for Increasing Accuracy and Precision. Ho-kwang Mao Carnegie Institution of Washington. Pressure Calibration Workshop January 26-28, 2007. Different Challenges in Different P-T Ranges. 2. 1- 100 GPa 10 MPa – 1 GPa
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Pressure Calibration in DAC -- Challenges for Increasing Accuracy and Precision Ho-kwang Mao Carnegie Institution of Washington Pressure Calibration Workshop January 26-28, 2007
Different Challenges in Different P-T Ranges 2 • 1- 100 GPa • 10 MPa – 1 GPa • 100- 300 GPa • High temperatures
Topics 3 • Primary calibration (accuracy) • Secondary calibration (precision) • Hydrostaticity • X-ray diffraction (axial and radial) • Optical spectroscopy (Brillouin, Raman, fluorescence) • Inelastic x-ray scattering spectroscopy
Goals 4 • Primary calibration (accuracy) • 1- 100 GPa P/P = ±1% • 100- 300 GPa P/P = ±1% • High temperatures -- at 100 GPa-2500 K P/P = ±1% • Secondary calibration (precision) • 10 MPa – 1 GPa P = ±5 MPa • 1- 100 GPa P/P = ±0.2% • 100- 300 GPa P/P = ±0.2%
Goals 4 • Primary calibration (accuracy) • 1- 100 GPa P/P = ±1% • 100- 300 GPa P/P = ±1% • High temperatures -- at 100 GPa-2500 K P/P = ±1% • Secondary calibration (precision) • 10 MPa – 1 GPa P = ±5 MPa • 1- 100 GPa P/P = ±0.2% • 100- 300 GPa P/P = ±0.2%
Primary calibration requires measurements of two independent functions related to pressure. 5 • Examples: • F and A – free rotation piston-cylinder • US and UP – shock Hugoniot • V and – DACV2 = K/K = dP/dP = V2d.
Primary calibration requires measurements of two independent functions related to pressure. 5 • Examples: • F and A – free rotation piston-cylinder • US and UP – shock Hugoniot • V and – DACV2 = K/K = dP/dP = V2d.
Goals 6 • Primary calibration (accuracy) • 1- 100 GPa P/P = ±1% • 100- 300 GPa P/P = ±1% • High temperatures -- at 100 GPa-2500 K P/P = ±1% • Secondary calibration (precision) • 10 MPa – 1 GPa P = ±5 MPa • 1- 100 GPa P/P = ±0.2% • 100- 300 GPa P/P = ±0.2%
Pressure calibration, DP/P ±1% 6 Zha, Mao, Hemley, PNAS (2000) Ruby fluorescence shift Calibrated by MgO P-r EOS (Secondary) r from x-ray diffraction Vffrom Brillouin scattering P-r EOS by integration (Primary)
Goals 10 • Primary calibration (accuracy) • 1- 100 GPa P/P = ±1% • 100- 300 GPa P/P = ±1% • High temperatures -- at 100 GPa-2500 K P/P = ±1% • Secondary calibration (precision) • 10 MPa – 1 GPa P = ±5 MPa • 1- 100 GPa P/P = ±0.2% • 100- 300 GPa P/P = ±0.2%
Secondary Calibration of Six Metals Dewaele, Loubeyre, Mezouar, PRB (2004) Ruby fluorescence shift Calibrated by MgO P-r EOS (Secondary) XRD, Dr/r ±0.2%, DP/P ±1%
Goals 12 • Primary calibration (accuracy) • 1- 100 GPa P/P = ±1% • 100- 300 GPa P/P = ±1% • High temperatures -- at 100 GPa-2500 K P/P = ±1% • Secondary calibration (precision) • 10 MPa – 1 GPa P = ±5 MPa • 1- 100 GPa P/P = ±0.2% • 100- 300 GPa P/P = ±0.2%
High T Primary Calibration Using V and 13 Problem: KS = (1 + agT) KT Difference ~10% at 3000 K introduces >1% error A practical alternative is to combine 300 K primary calibration and high resolution high P-T XRD
Post-perovskite P-V-T 14 W. Mao et al, submitted (2007) (VT – V300)/V300 Temperature (K) Volume (Å3) 2000 K 1400 K Fs20 ppv 300 K Pressure (GPa)
Goals 15 • Primary calibration (accuracy) • 1- 100 GPa P/P = ±1% • 100- 300 GPa P/P = ±1% • High temperatures -- at 100 GPa-2500 K P/P = ±1% • Secondary calibration (precision) • 10 MPa – 1 GPa P = ±5 MPa • 1- 100 GPa P/P = ±0.2% • 100- 300 GPa P/P = ±0.2%
16 Biomaterials -- bacteria and virus Single-Crystal Diffraction of Cow Pea Mosaic Virus - BIOCHEMICAL REACTIONS IN HYDROTHERMA FLUIDS - LIFE IN EXTREME ENVIRONMENTS (>1600 MPa) 350 MPa [Lin et al., Acta Crystal. D61, 737(2005)] • PRESSURE EFFECTS ON • STRUCTURE-FUNCTION RELATIONS [Sharma et al., Science 295, 1514 (2002)]
d-spacing, Å Intensity Energy, keV 17 Hydrogen storage in clathrate H2-2H2O S-II clathrate-- A clean and efficient material for hydrogen storage W Mao et al,Science (2002)--Synthesis S-II at HP and quenched to low PT; Lokshin et al,PRL (2004)--Identification of H2 in S-II cages with neutron; Florusse et al, Science (2004)--Stabilized to 280K at 1 bar HH-sII H2+H2O 0.2 GPa 10 kPa 240 280 77 K 110 140
Goals 18 • Primary calibration (accuracy) • 1- 100 GPa P/P = ±1% • 100- 300 GPa P/P = ±1% • High temperatures -- at 100 GPa-2500 K P/P = ±1% • Secondary calibration (precision) • 10 MPa – 1 GPa P = ±5 MPa • 1- 100 GPa P/P = ±0.2% • 100- 300 GPa P/P = ±0.2%
Spin transition of iron in magnesiowüstite 19 High Pressure Experiments Challenge Existing Understanding of Seismic Waves in Deep Earth The crushing pressures in the lower mantle squeeze atoms and electrons so closely together that they interact differently from under normal conditions, even forcing spinning electrons to pair up in orbits. In theory, seismic-wave behavior at those depths may result from the vice-gripping pressure effect on the electron spin-state of iron in lower-mantle materials. Carnegie’s team performed ultra high-pressure experiments on the most abundant oxide material there, magnesiowüstite (Mg,Fe)O, and found that the changing electron spin states of iron in that mineral drastically affect the elastic properties of magnesiowüstite. The research may explain the complex seismic wave anomalies observed in the lowermost mantle. Normalized volume of magnesiowüstite, (Mg0.83,Fe0.17)O, as a function of pressure at 300 K. Jung-Fu Lin, Viktor V. Struzhkin, Steven D. Jacobsen, Michael Y. Hu, Paul Chow, Jennifer Kung, Haozhe Liu, Ho-kwang Mao and Russell J. Hemley; "Spin transition of iron in magnesiowüstite in the Earth's lower mantle" Nature 436, 377-380 (21 July 2005)
Goals 20 • Primary calibration (accuracy) • 1- 100 GPa P/P = ±1% • 100- 300 GPa P/P = ±1% • High temperatures -- at 100 GPa-2500 K P/P = ±1% • Secondary calibration (precision) • 10 MPa – 1 GPa P = ±5 MPa • 1- 100 GPa P/P = ±0.2% • 100- 300 GPa P/P = ±0.2%
Topics 21 • Primary calibration (accuracy) • Secondary calibration (precision) • Hydrostaticity • X-ray diffraction (axial and radial) • Optical spectroscopy (Brillouin, Raman, fluorescence) • Inelastic x-ray scattering spectroscopy
Shear strength of argon Primary calibration needs to use He medium Mao, et al, J. Phys.: Cond. Mat. (2006)
Topics 23 • Primary calibration (accuracy) • Secondary calibration (precision) • Hydrostaticity • X-ray diffraction (axial and radial) • Optical spectroscopy (Brillouin, Raman, fluorescence) • Inelastic x-ray scattering spectroscopy
Attaining DVF /VF ± 1% 24 • Ultrasonic measurements • Nuclear resonant inelastic x-ray scattering • Brillouin Spectroscopy • Inelastic x-ray scattering spectroscopy
Attaining DVF /VF ± 1% 25 • Ultrasonic measurements to 50-300 GPa? • Nuclear resonant inelastic x-ray scattering • Brillouin Spectroscopy • Inelastic x-ray scattering spectroscopy
Attaining DVF /VF ± 1% 27 • Ultrasonic measurements • Nuclear resonant inelastic x-ray scattering • Brillouin Spectroscopy • Inelastic x-ray scattering spectroscopy
Brillouin Spectroscopy 28 • Single crystalVf accuracy ±1% • PolycrystallineVf accuracy 3-10%
Inelastic x-ray scattering spectroscopy (IXSS) Poly-xtal hcp-Fe to over 100 GPa Single-xtal Co at 39 GPa Antonangeli et al, PRL 2005 Determines phonon dispersion Antonangeli et al., EPSL 2004 Fiquet et al.,Science 2001 Antonangeli et al, PRL 2005
30 Inelastic x-ray scattering spectroscopy (IXSS) hcp-Fe at 52 GPa 35XU, SPring-8 W. Mao et al, in prep. Improve energy resolution from 6 meV to 1 meV to get to DVF /VF ± 1%
High Res. XRD with panoramic DAC UNICAT, 34-ID, APS, ANL r /r ctnqDq Going from 2q = 10º to 2q = 90º,r/rimproves 10x !
Summary: Achievable Goals 32 • Primary calibration (accuracy) • Hydrostaticity of He? P/P = 0.2-1%? • Single-xtl Brillouin scattering or single-xtl ixss to 100- 300 GPa Vf/ Vf= ±1% • Polycrystalline XRD to 100- 300 GPa and 100 GPa-2500 K r /r= ±0.2% P/P = ±1% • Secondary calibration (precision) • High resolution XRD at 10 MPa- 300 GPa r /r= ±0.02% P/P = ±0.2% • Optical calibration P/P = ±0.2%