Temperature and rate effects in ramp-wave compression freezing of liquid water

Abstract

Quasi-isentropic compression of liquid water beyond 5 GPa rapidly creates ice VII on 1-10 ns time scales. The onset of this phase transition can be modified by changing the initial temperature of the liquid sample and/or the compression rate. These effects were studied using the Sandia Thor-64 pulsed power machine. Increasing the initial temperature pushes freezing above the previously reported 7 GPa metastable limit. Slower compression allows freezing to occur below the metastable limit, though the compression rate has a greater effect at an elevated temperature than at room temperature.