DAC Center at NSLS H' K' Mao spokesperson

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DAC Center at NSLSH. K. Mao (spokesperson) R.
J. Hemley (co-spokesperson) Q. Z. Guo
(X17B3) Jingzhu Hu (X17C) Z. X. Liu
(U2A) Geophysical Laboratory, Carnegie
Institution of Washington COnsortium for
Materials Properties Research in Earth Sciences
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DAC Center at NSLS
X17B
X17C
X-RAY
IR
U2A
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NSLS has a very bright future in the next decade
X-Ray Brilliance
X17 Superconducting Wiggler White Beam Flux
IR Brilliance
Xray Spectroscopy
Time Resolved XRD
Amorphous
Xray Diffraction
Single-crystal XRD
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Capabilities

• X17B3 beam line
• On-line laser-heating
• Cryogenic conditions
• EDXD
• ADXD
• Microbeam lt 10 microns
• 100 days/year beam time

• X17C beam line
• EDXD
• ADXD
• lt10 microns white beam
• Sagittal Laue focusing mono
• 200 days/year beam time

• U2A beam line
• Cryogenic conditions
• Diffraction limited IR microscopy
• On-line Raman
• 200 days/year beam time

• On-site laboratory
• Ruby P-calibration
• Portable on-line Raman
• Sample prep
• Cryogenic gas loading
• Supporting all HP beamlines

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Firsts

• Dedicated high-pressure XRD beamline
• Dedicated high-pressure IR beamline
• Integration of XRD and laser-heating high P-T
• Double-sided laser heating
• Resistive heating and XRD above 100 GPa-1000 K
• Integration of HP XRD, IR, on-line Raman at
  cryogenic T
• Side diffraction for HP elasticity tensor and
  rheology
• Single crystal diffraction above 20 GPa (to 60
  GPa)
• XRD of nanometer-size single crystal
• XRD of amorphous structure at high P
• Pressure calibration based on volume and
  elasticity

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Hydrogen clathrate, H2-2H2O
Examples of Current Research Clathrates
220 MPa 234 K
Xe Clathrates
X-ray Diffraction
Sanloup et al, PNAS 2002
Xe-Silicates
IR Absorption Spectroscopy
Sanloup et al, GRL 2002
W Mao et al, Science 2002
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Ultrahigh-pressure metamorphism and meteorite
impact metamorphism
New Mineral, Tuite, in shocked meteorite
Xie et al, GCA 2002
Two New Minerals, high pressure phases of
chromite, in DAC and in shocked meteorite
Sobolev et al, PNAS 2000
Chen et al, in press
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High Resolution Diffraction in Helium Medium
Mg0.1Fe0.9O K0155?10 GPa K03.6?0.8
Mao et al, JPCM 2002
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Rheology of Core Mantle Minerals
Merkel et al, EPSL 2003
Merkel et al, JGR 2002
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54 GPa 220 GPa
Plasticity of Iron and the Earths Inner Core
EXP.
THEORY

• Basal slip is dominant deformation mechanism
• Aggregate VP anisotropy is 4-18 in core
• Earth lt4 temperature? alloys?

Wenk et al. Nature 405, 1044 (2000)
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Laser-Heating
Williams et al. (1987)
Boehler (1993)
Shen et al., Geophys. Res. Lett. 25, 373
(1998) Ma et al., to be published
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Large Volume DAC Big MAC
XRD, Raman, IR and laser -heating with 10 carat
moissanite anvil cell Xu et al, JPCM 2002
Rapid Growth of Single-Crystal Diamond by
Homoepitaxial CVD Yan, et al, PNAS 2002
XRD with CVD DAC to 230 GPa Manuscript in prep.
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Planetary Gases and Ices
HYDROGEN
Structure/bonding/dynamics of of hydrogen and
H2O from XRD, IR, and Raman
Goncharov et al, PNAS 2002
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Beamtime and Users

• Users write proposals to NSLS
• Two tracks
• NSLS review committee gives ratings and assigns
  25 of the beam time
• If a COMPRES member does not receive beamt ime
  from NSLS, it will be reviewed for consideration
  for PRT beam time
• So far, 100 of COMPRES member proposals have
  been awarded beam time through one of the above
  two tracks. We could still do much better because
  many times more people in the COMPRES community
  could be greatly benefited from this
  state-of-the-art facility but have not learned
  about the capabilities and do not know how to get
  started.

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Future Goals with COMPRES

• DAC/NSLS focuses on SR development and operation.
  We rely on COMPRES to reach out the greater user
  community and coordinate user needs to
  appropriate facilities.
• COMPRES handles 100 of the DAC/NSLS PRT beam
  time and financial responsibilities to satisfy
  the needs of the greater community.
• Improving COMPRES and DAC/NSLS communication

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DAC/NSLS Budget and Resources

• Yearly operation budget (including beamline staff
  salaries, maintenance, and upgrade) 600 K
  (300 K from COMPRES)
• Total beam time from 3 beamlines 500 days/year
• Cost of beam time 1200/day
• This is among the most cost-efficient and most
  productive high-pressure beamline in the world.
  In comparison
• Multi-anvil at NSLS gt 5000/day
• GSECARS beam time 5000/day

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Acknowledgments
Beamline Development Tom Duffy Guoyin
Shen Yanzhang Ma Maddury Somayazulu Michael
Hanfland Ming Li
Original PRT Members Earl Skelton- -- NRL Dave
Schiferl -- LANL Jagan Akella -- LLNL Paul
McMillan -- ASU
Funding Sources NSF-EAR NSF-DMR DOE-DP DOE-BES NAS
A Navy Carnegie
Technical Help Larry Carr Peter Eng Larry
Finger Alexander Goncharov Gwyn Williams Yan
Wu Mark Rivers Users