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DOE OSTI · 2404486

Simultaneous compression of NaCl, Au, and ruby: toward mutually consistent pressure scales

Wang, Yanbin·Shen, Guoyin·Smith, Jesse S.
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Abstract

Here, we evaluate pressure consistency of equations of state (EOS) for NaCl and Au at 300 K. The simultaneous measurements of unit-cell volumes (V) with ruby R1 line shifts (Δλ) in a helium (He) loaded diamond cell effectively remove potential systematic errors. Compression and decompression data were automatically collected at 1 sec interval, yielding a dense dataset with >8,000 (V, Δλ) pairs each for NaCl and Au. Solidification of He has noticeable effects on both V and Delta lambda (hence P). Only data up to similar to 14 GPa, or 6000 (V, P) pairs, can be considered hydrostatic within the resolution. The P-V data are fitted to the Rydberg-Vinet and the 3 rd order Birch-Murnaghan EOS. Predicted pressures of these EOSs agree with those given by the Ruby2020 ruby scale to within +/- 0.05 GPa. Overall, pressures predicted by the Rydberg-Vinet EOS are in better agreement with the average of commonly used NaCl and Au pressure scales.

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38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRYBirch-Murnaghan equation of stateHigh pressure X-ray diffractionRydberg-Vinet equation of statehydrostaticityruby pressure scales

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Wang, Yanbin, Shen, Guoyin, Smith, Jesse S.. 2024-01-09. Simultaneous compression of NaCl, Au, and ruby: toward mutually consistent pressure scales. https://doi.org/10.1080/08957959.2023.2301561

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