Examination of the Metastable Phase Generated During Water Crystallization

Abstract

Hexagonal and cubic phases have been observed under atmospheric pressure as an ice crystalline phase. No study has reported the preparation of a cubic phase by directly freezing bulk water or by directly cooling the hexagonal phase. We hypothesize that the cubic phase is initially formed upon the crystallization of water and that it subsequently transitions to a hexagonal phase at a momentary rate. When pure water was used, it was not possible to capture the process of transferring to the hexagonal phase through the cubic phase at an integration interval of one second. However, when a 40 wt% aqueous glucose solution was used, it was possible to capture the process of transitioning from the supercooled liquid to the hexagonal phase through the cubic phase with an integration time of one second. This result is considered to indicate that the pure water may be instantaneously transferred from the supercooled liquid through the cubic phase to the hexagonal phase.