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Updated: May 30, 2026
16:24
Controlling the Size, Shape and Stability of Supramolecular Polymers in Water
Published on: August 2, 2012
Dynamically slow processes in supercooled water confined between hydrophobic plates
Giancarlo Franzese1, Francisco de Los Santos
1Departamento de Física Fundamental, Universidad de Barcelona, Diagonal 647, Barcelona 08028, Spain.
Summary
Confined water exhibits pressure-dependent dynamics. At high pressure, water dewets rapidly. At lower pressures, hydrogen bond ordering and critical point proximity create complex dynamics and slower dewetting.
Area of Science:
- Physical Chemistry
- Soft Matter Physics
Background:
- Water's unique hydrogen bond network governs its properties.
- Confining water alters its behavior compared to bulk water.
Purpose of the Study:
- Investigate water dynamics between hydrophobic surfaces at low temperatures.
- Correlate pressure-induced changes in water behavior with hydrogen bond dynamics.
Main Methods:
- Simulations of water confined between hydrophobic flat surfaces.
- Analysis of correlation functions and dewetting processes at varying pressures.
Main Results:
- High pressure: inhibited hydrogen bond network, rapid dewetting via large cavity formation.
- Lower pressure: non-exponential correlation, heterogeneity due to hydrogen bond ordering, influenced by liquid-liquid critical point.
- Very low pressure: gradual network formation, dynamical arrest, dewetting via small cavities.
Conclusions:
- Water's confined dynamics are highly sensitive to pressure and hydrogen bond network structure.
- The proximity to a liquid-liquid critical point significantly impacts water's relaxation timescales and heterogeneity.
- Dewetting mechanisms vary dramatically with pressure, from large single cavities to numerous small ones.
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