Thermal expansion of recovered high-pressure ice polymorphs

The ambient-pressure phase of ice is a well-known example of a molecular solid that exhibits negative volume thermal expansion below 60 K. In a recent study carried out on HRPD we determined that ice III displays negative area expansion below 45 K, and also obtained some evidence that ice V has negative linear expansion at low temperature. Due to the fundamental interest in this type of anomalous thermo-elastic property and both the ubiquity and variety of ice polymorphs, a thorough characterisation of the thermal expansion of other high-pressure ice phases is warranted. This proposal seeks to determine the thermal expansion to high precision of ices II, V and VI in the range 10 - 150 K, along with complementary structural information. These will be prepared offline in a piston-cylinder cell and then recovered under liquid nitrogen for analysis on HRPD.