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Updated: Aug 5, 2026
09:09
Layer-by-layer Synthesis and Transfer of Freestanding Conjugated Microporous Polymer Nanomembranes
Published on: December 15, 2015
Layering Governs Phase Transitions in Nanoconfined Water
Yuntao Du1, Mehdi Neek-Amal2,3, Bofeng Bai1
1State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, China.
The Journal of Physical Chemistry Letters
|July 27, 2026
Summary
Water
Area of Science:
- Physical Chemistry
- Materials Science
- Nanotechnology
Background:
- Water exhibits unique phase behavior under molecular-scale confinement.
- Layering of water molecules is crucial for its thermodynamic properties.
- Oscillations in properties like diffusivity with channel height are known.
Purpose of the Study:
- To elucidate the microscopic origins of water's phase transitions in confined geometries.
- To identify distinct pathways governing freezing and melting in nanochannels.
- To develop a theoretical model explaining confinement-induced ordering.
Main Methods:
- Extensive molecular dynamics simulations were employed.
- Analysis focused on the hydrogen-bond network rearrangements.
- A minimal Landau free energy model was developed.
Main Results:
- Two distinct transition pathways identified: constant-layer phase transition (CLPT) and variable-layer phase transition (VLPT).
- CLPT involves gradual strengthening of intralayer hydrogen bonds.
- VLPT involves abrupt ice melting due to layer-splitting instability.
- Periodic freezing-melting cycles observed, forming integer-layer ice bands.
- A Landau model with an oscillatory coefficient successfully reproduced phase boundaries.
Conclusions:
- Layering in confined water dictates distinct freezing-melting mechanisms.
- Geometric commensurability between water molecules and confinement drives oscillatory behavior.
- Layering acts as a thermodynamic field influencing ordering transitions in confined liquids.
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