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Measurement and correlation of the ( p, ρ, T) relation of sulphur hexafluoride (SF 6). II. Saturated-liquid and saturated-vapour densities and vapour pressures along the entire coexistence curve

“…CRITICAL TEMPERATURE Table 4 shows a compilation of selected published values for the critical temperature of pure sulphur hexafluoride; the estimated experimental uncertainties are also given. The highly accurate critical temperature value of Kurzeja et al (10) agrees very well, within its uncertainty of ±0.002 K, with the critical temperature of Ivanov, (29) and it also agrees within 0.012 K with the value of Makarevich et al (30) (see table 4). However, based on our experience, the uncertainty of ±0.0002 K, claimed by Ivanov (29) and Makarevich et al (30) seems to be considerably small.…”

“…In the immediate vicinity of the critical point, the behaviour of the thermal properties of pure fluids are influenced by the gravity of earth. This behaviour of pure fluids under the influence of gravity was recently investigated thoroughly within our group by Kurzeja et al (10) and Kurzeja and Wagner. (2) It has been found that the gravity effect influenced the course of the saturation curve in a temperature range from T c to about 0.090 K below T c in the case of SF 6 .…”

“…This particular behaviour of fluids in the critical region will be discussed in detail by Kurzeja and Wagner. (2) Using their comprehensive and highly accurate ( p, ρ, T ) measurements in the critical region, Kurzeja et al (10) have determined the critical temperature of SF 6 to be: T c = (318.7232±0.002) K.…”

Measurement and correlation of the (p, ρ, T) relation of sulphur hexafluoride (SF 6). I. The homogeneous gas and liquid region in the temperature range from 225 K to 340 K at pressures up to 12 MPa

“…(2) These measurements were carried out in our group by means of a new multi-cell apparatus specially developed for highly accurate ( p, ρ, T ) measurements in the immediate vicinity of the critical point. (45,46) In this immediate critical region our new measurements were carried out only in a selected part in such a way that they overlapped with the comprehensive data set of Kurzeja and Wagner (2) in the density range from about 600 kg · m −3 ρ 900 kg · m −3 . Hence, on the five isotherms measured between T = 318.713 K and 318.938 K, only the density range ρ 650 kg · m −3 and ρ 850 kg · m −3 was measured and the range between 650 kg · m −3 and 850 kg · m −3 was omitted.…”

D. Yu. Ivanov: Critical Behavior of Non-Ideal Systems

“…He highlights data from Wagner's group as evidence of a second crossover to classical behavior [7]. Wagner's group measured height-averaged pressure differences between 1 cm tall sulfur hexafluoride (SF 6 ) samples near T c .…”