Thermal expansivity, bulk modulus, and melting curve of H[sub 2]O--ice VII to 20 GPa

Journal Article · Fri Oct 01 04:00:00 EDT 1993 · Journal of Chemical Physics; (United States)

DOI:https://doi.org/10.1063/1.465980· OSTI ID:6299688

Fei, Y; Mao, H; Hemley, R J ^[1]

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1. Geophysical Laboratory and Center for High Pressure Research, Carnegie Institution of Washington, Washington, DC 20015 (United States)

Equation of state properties of ice VII and fluid H[sub 2]O at high pressures and temperatures have been studied experimentally from 6 to 20 GPa and 300--700 K. The techniques involve direct measurements of the unit-cell volume of the solid using synchrotron x-ray diffraction with an externally heated diamond--anvil cell. The pressure dependencies of the volume and bulk modulus of ice VII at room temperature are in good agreement with previous synchrotron x-ray studies. The thermal expansivity was determined as a function of pressure and the results fit to a newly proposed phenomenological relation and to a Mie--Grueneisen equation of state formalism. The onset of melting of ice VII was determined directly by x-ray diffraction at a series of pressures and found to be in accord with previous volumetric determinations. Thermodynamic calculations based on the new data are performed to evaluate the range of validity of previously proposed equations of state for fluid water derived from static and shock-wave compression experiments and from simulations.

• DOE Contract Number: AC02-76CH00016
• OSTI ID: 6299688
• Journal Information: Journal of Chemical Physics; (United States), Journal Name: Journal of Chemical Physics; (United States) Vol. 99:7; ISSN JCPSA6; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360602 -- Other Materials-- Structure & Phase Studies
360606* -- Other Materials-- Physical Properties-- (1992-)
COHERENT SCATTERING
DIFFRACTION
EQUATIONS
EQUATIONS OF STATE
EXPANSION
HIGH PRESSURE
HYDROGEN COMPOUNDS
ICE
MELTING
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
SCATTERING
TEMPERATURE RANGE
TEMPERATURE RANGE 0273-0400 K
TEMPERATURE RANGE 0400-1000 K
THERMAL EXPANSION
THERMODYNAMICS
VOLUME
WATER
X-RAY DIFFRACTION