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Updated: Jun 25, 2026
06:26
Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
On thin ice: surface order and disorder during pre-melting.
1Department of Chemistry, Christopher Ingold Building, University College London, 20 Gordon Street, London, UK.
Faraday Discussions
|February 21, 2009
Summary
Molecular dynamics simulations reveal ice surface changes with temperature. Above 270 K, ice Ih (0001) surfaces destructure and melt, with a nanometer-thick liquid-like layer forming near the melting point.
Area of Science:
- Physical Chemistry
- Materials Science
- Surface Science
Background:
- Understanding ice surface behavior is crucial for various applications.
- The structure of ice Ih (0001) surface is sensitive to thermal fluctuations.
Purpose of the Study:
- To investigate the effect of temperature on the structure of the ice Ih (0001) surface.
- To identify temperature-induced structural changes and melting phenomena.
Main Methods:
- Molecular dynamics simulations of an ice slab.
- Analysis of surface self-interstitials, vacancies, and molecular mobility.
Main Results:
- At 200 K, surface self-interstitials form from the outermost bilayer.
- At ~250 K, vacancies appear, exposing dangling hydrogen bonds.
- Above 270 K, surface destructuring and melting occur, forming a ~1 nm liquid-like layer.
Conclusions:
- Melting initiates 10-20 K below the bulk melting point.
- Surface proton distribution influences thermodynamic stability and pre-melting.
- Hotspots with high dangling proton density may enhance catalytic activity.
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