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Updated: Jul 14, 2026
09:32
Cooling Rate Dependent Ellipsometry Measurements to Determine the Dynamics of Thin Glassy Films
Published on: January 26, 2016
Water Behaviour: glass transition in hyperquenched water?
Ingrid Kohl1, Luis Bachmann, Erwin Mayer
1Institute of General, Inorganic and Theoretical Chemistry, University of Innsbruck, 6020 Innsbruck, Austria. ingrid.kohl@uibk.ac.at
Nature
|May 27, 2005
Summary
Amorphous glassy water heated above 140 K behaves as an ultraviscous liquid, not remaining glassy until crystallization. This finding clarifies the anomalous properties of supercooled water.
Area of Science:
- Physical Chemistry
- Materials Science
Background:
- The phase behavior of amorphous solid water (ASW) upon heating remains debated.
- Specifically, it is unclear if ASW remains glassy until crystallization or transitions into a supercooled liquid state around 140-150 K.
Discussion:
- This study utilizes differential scanning calorimetry (DSC) to investigate hyperquenched water (HQW) deposited at 140 K.
- Experimental results demonstrate that HQW behaves as an ultraviscous liquid, challenging previous claims of glassy behavior up to crystallization.
Key Insights:
- Hyperquenched water exhibits liquid-like properties at temperatures previously thought to be within the glassy state.
- The observed behavior aligns with theoretical predictions of the liquid-to-glass transition, with a glass-to-liquid transition-onset temperature (Tg) around 136 K.
Outlook:
- Further characterization of the ultraviscous liquid's properties is crucial for understanding the anomalous behavior of supercooled water.
- These findings necessitate a re-evaluation of models describing water's phase transitions and glassy states.
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