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Updated: Dec 13, 2025
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Supercritical Nitrogen Processing for the Purification of Reactive Porous Materials
Published on: May 15, 2015
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Supercritical Water is not Hydrogen Bonded
Philipp Schienbein1, Dominik Marx1
1Lehrstuhl für Theoretische Chemie, Ruhr-Universität Bochum, 44780, Bochum, Germany.
Angewandte Chemie (International Ed. in English)
|August 5, 2020
Summary
Supercritical water does not exhibit hydrogen bonds. Molecular dynamics simulations show that hydrogen bond lifetimes are shorter than vibration periods, indicating van-der-Waals forces dominate in this phase.
Area of Science:
- Physical Chemistry
- Materials Science
- Chemical Physics
Background:
- Water's unique properties, including its tetrahedral structure, are attributed to hydrogen bonds.
- The behavior of water under supercritical conditions remains an area of active research.
Purpose of the Study:
- To investigate the presence and nature of hydrogen bonds in supercritical water.
- To understand the structural and dynamic evolution of water's hydrogen bond network from ambient to supercritical conditions.
Main Methods:
- Utilizing extensive ab initio molecular dynamics simulations.
- Systematically monitoring the H-bond network evolution across a range of temperatures and pressures, including supercritical conditions.
Main Results:
- Hydrogen bond lifetimes in supercritical water are significantly shorter than the periods required for H-bond vibrations.
- Low-frequency intermolecular vibrations in supercritical water are accurately described by isotropic van-der-Waals interactions alone.
Conclusions:
- Supercritical water is not a hydrogen-bonded fluid.
- The dominant interactions in supercritical water are van-der-Waals forces, not hydrogen bonds.
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