Pressure media for high pressure experiments, Daphne Oil 7000 series

Characterization of a new pressure medium Daphne Oil 7575 using a set of three manganin coils, a superconducting temperature of lead and the response of two perpendicular strain-gages down to low temperatures is presented. A complementary study of Daphne Oil 7474 and Daphne Oil 7373 employing identical methods is included as well. Temperature dependence of the solidification point of Daphne Oil 7575 follows the behavior of its predecessor, Daphne Oil 7474, shifted to slightly higher pressure by about 0.2 GPa. Both Daphne Oil 7474 and Daphne Oil 7575 exhibit larger pressure decrease - between the pressure at room temperature and that at low temperature - than Daphne Oil 7373. On the other hand the solidification pressure of the two media is more than 1 GPa higher than for their ancestor, making them more suitable for experiments in frequently used piston pressure cells with nominal pressure of about 3 GPa.