Water under pressure
1Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550, USA.
Physical Review Letters
|October 6, 2000
Summary
High pressure and temperature alter water structure, weakening hydrogen bonds and changing oxygen coordination. Simulations show no dissociation near freezing point, offering new data for experiments.
Area of Science:
- Physical Chemistry
- Materials Science
Background:
- Understanding water's behavior under extreme conditions is crucial for various scientific fields.
- Previous studies have explored water's phase transitions and structural changes at high pressures.
Purpose of the Study:
- To investigate the structural and hydrogen bonding changes in water under high pressure using first-principles molecular dynamics.
- To explore the nondissociative regime of water at 10 GPa and 600 K.
Main Methods:
- First-principles molecular dynamics simulations.
- Analysis of hydrogen bonding, oxygen-oxygen coordination, and electronic density of states.
Main Results:
- Water at 10 GPa and 600 K shows significant structural alterations compared to ambient conditions.
- No appreciable molecular dissociation was observed, but hydrogen bonding weakened.
- Increased oxygen atom coordination and notable changes in electronic states near the Fermi level were identified.
Conclusions:
- High pressure significantly modifies water's structure and hydrogen bond network without dissociation near its freezing point.
- The study provides valuable structural data for validating future experimental findings on pressurized water.
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