Detection of the Metastable Ice Phase during Water Crystallization

Area of Science:

• Materials Science
• Physical Chemistry
• Crystallography

Background:

• Ice crystals exist in hexagonal (stable) and cubic (metastable) phases under atmospheric pressure.
• Understanding ice phase transitions is crucial for various scientific and industrial applications.

Purpose of the Study:

• To investigate the hypothesis that water initially crystallizes into the cubic phase before transforming into the hexagonal phase.
• To identify conditions and substances that promote or inhibit the cubic-to-hexagonal ice phase transition.

Main Methods:

• Investigated aqueous solutions of glucose (40% and 50% w/w) and ammonium hydrogen sulfate (40% w/w).
• Examined emulsified water under freezing conditions.
• Utilized techniques to detect ice phase formation and transitions within a 1-second interval.

Main Results:

• The cubic-to-hexagonal ice phase transition was observed in 40% (w/w) glucose solution.
• Cubic ice formed in 50% (w/w) glucose solution did not transition to the hexagonal phase.
• The cubic phase was confirmed in 40% (w/w) ammonium hydrogen sulfate solution, but not in emulsified water.

Conclusions:

• The cubic-to-hexagonal ice phase transition occurs in specific aqueous solutions upon freezing.
• The transition process was not clearly observed in emulsified water under the experimental conditions.