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Updated: Jan 30, 2026
16:24
Controlling the Size, Shape and Stability of Supramolecular Polymers in Water
Published on: August 2, 2012
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Liquid water is a dynamic polydisperse branched polymer.
Saber Naserifar1, William A Goddard2
1Materials and Process Simulation Center, California Institute of Technology, Pasadena, CA 91125.
Summary
A new quantum mechanics-based force field, RexPoN, accurately predicts water properties. It reveals water
Area of Science:
- Computational chemistry
- Physical chemistry
- Materials science
Background:
- Water's unique properties are crucial for life and materials science.
- Existing models struggle to accurately capture water's behavior across different states.
- A precise force field is needed to simulate water's complex hydrogen-bonding network.
Purpose of the Study:
- To develop a novel, quantum mechanics-based force field for water.
- To accurately predict water's thermodynamic and structural properties.
- To elucidate the role of hydrogen bonding in water's behavior.
Main Methods:
- Developed the RexPoN force field using quantum mechanics calculations.
- Simulated water properties including melting point, enthalpy of vaporization, density, entropy, and dielectric constant.
- Analyzed strong hydrogen bond (SHB) dynamics, lifetimes, and network structure.
Main Results:
- RexPoN accurately predicts key water properties, closely matching experimental values.
- Observed a significant drop in SHBs upon melting and a decrease with increasing temperature.
- Identified a dynamic, branched polymer structure formed by SHBs, with implications for water's unique characteristics.
Conclusions:
- The RexPoN force field provides a highly accurate model for water.
- Water's properties can be understood through a dynamic, branched polymer paradigm.
- This new perspective may explain phenomena like supercooled critical points and impact biomolecular simulations.
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