A new pressure medium, Daphne 7676, with solidification pressure of 5 GPa at 300 K and low melting point of around 110 K at ambient pressure

A recently developed pressure medium ‘Daphne 7676’ increases considerably the solidification pressure (Ps) at room temperature from 3.7 GPa (Daphne 7474) and 4.0 GPa (Daphne 7575) to 5 GPa. Moreover, Daphne 7676 is found to show a viscosity more than one order of magnitude lower than the preceding materials. Even after solidified above 5 GPa, the medium appears to have exceptionally low shear strength, with evidence of some relaxations over time-scales of hours. Furthermore, at ambient pressure, Daphne 7676 is found to show freezing/melting temperature (Tm) of 113 K and a glass transition (Tg) at approximately 110 K. These values are considerably lower than for Daphne 7474, with Tm = 150 K and Tg = 140 K. Considering that 113 K is close to the critical temperature Tc (110 K) of Bi-high-Tc superconductors, for example, this fluid may have widespread applications in high pressure research but potentially also in bio and life-sciences.