Report on the First International Pressure Calibration Workshop.

Abstract

Sixty seven scientists, representing the diamond anvil and multianvil communities from six countries , attended. Thirty seven papers were presented in three oral sessions titled, "Equations of state and the absolute pressue scale", "Multianvil calibration", and "Diamond anvil and other studies" and eight papers were presented as posters. In a final discussion period, it was decided too publish a multi-authored paper describing the Preliminary International Pressure Scale (PIPS-97). It was decided that this scale should contain consensus pressure calibration phase transitions at room temperature, equations for well-characterized phase transitions at high temperatures and pressures, and the equations of state for NaCI , Au, and MgO. [pressure calibration, diamond anvil, multianvil, equation of state, X-ray diffraction]

Toward an international practical pressure scale: A proposal for an IPPS ruby gauge (IPPS-Ruby2020)

“…By converting the V-Δλ data to P-Δλ relations using the EOS of NaCl [21,22,64], we obtain A = 1890(5) GPa from Brown's EOS for NaCl [21], A = 1848(6) GPa from Marcondes and Wentzcovitch's EOS [22], and A = 1833(4) GPa from Decker's EOS [64], all with B fixed at 5.5 and a similar pressure range of 0-12 GPa. Our constrained A-value, 1.87(1)x10 3 GPa, is generally consistent with those from NaCl data within the uncertainties in the EOS from different sources.…”

“…For diamond, the V-Δλ data are from [9]. The line is the fit in the form of A (Δλ/λ 0 )[1+B(Δλ/λ 0 )] with A=1870 GPa (fixed) and B=5.63 (3). The fit gives a root-mean-square value of 0.7 GPa in the pressure range up to 150 GPa.…”

“…A back-extrapolation of all the data (Mo, Cu, MgO, diamond) below 12 GPa according to Eq. (2) gives A = 1.87(1)x10 3 GPa, with the B value fixed at 5.5. Changing B by ±0.5 has negligible effect on the resultant A values (within ±2 GPa).…”

“…From 1982 to 1986, the group recommended a ruby pressure scale, the Decker equation of state for NaCl, and a set of pressure reference points for opaque anvils be used as practical pressure reference standards [1,2]. A decade later, the first international pressure calibration workshop was held in Japan in 1997, with a proposal of several reference points for pressure reference standards [3,4]. Since then, several major developments have occurred in high-pressure technology.…”

Pressure buffering in a diamond anvil cell

“…At high pressures and room temperature resistance changes accompanying phase transitions in metals such as Bi and Pb, or semi-conductor to metal transitions in ZnS or GaAs are often used as standards (e.g. Bean et al, 1986;Ito and Presnall, 1998). The pressures at which these transitions occur may be determined by careful experiments in special high-pressure apparatus in which the effects of friction are very well characterized (Getting and Burnley, 1994;Getting, 1998).…”