Evidence for a very slow transformation in ice VI at low temperatures

The high-frequency permittivity of ice VI decreases steadily at 123.1 K and increases again when warmed to 127.8 K. There is therefore a new transformation occurring slowly in this region. The transformation of samples of H2O, D2O, and 1% D2O in H2O was followed for 252 days, and it was not yet completed. The experimental conditions were within the region of stability of ice VI, so the transformation is not to a known phase of ice. It was too slow to be an ordering transformation determined by the dielectric relaxation time, and it is likely that a wholly new phase was being produced.