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Updated: Apr 25, 2026
08:16
Ice Generation and the Heat and Mass Transfer Phenomena of Introducing Water to a Cold Bath of Brine
Published on: March 13, 2017
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Decomposition and Terapascal phases of water ice
Chris J Pickard1, Miguel Martinez-Canales1, Richard J Needs2
1Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom.
Physical Review Letters
|August 29, 2014
Summary
Water ice (H2O) decomposes into hydrogen peroxide (H2O2) and a hydrogen-rich phase above 5 TPa. New complex water ice phases are stable between 0.8-2 TPa, impacting gas giant core erosion.
Area of Science:
- Planetary Science
- Materials Science
- Computational Chemistry
Background:
- Understanding the behavior of water ice (H2O) under extreme pressures is crucial for planetary science.
- Previous models have not fully captured the complex phase diagrams of H2O at terapascal (TPa) pressures.
Purpose of the Study:
- To computationally investigate the structural stability of water ice and H:O compositions at TPa pressures.
- To predict new phases and decomposition pathways of H2O under extreme conditions.
Main Methods:
- Utilized computational searches to explore stable and metastable structures of H2O and related compounds.
- Simulated material behavior at pressures exceeding 5 TPa.
Main Results:
- Predicted H2O decomposition into H2O2 and a hydrogen-rich phase above 5 TPa.
- Identified a stable hydrogen-rich phase relevant to gas giant core erosion.
- Discovered novel, complex water ice phases stable between 0.8-2 TPa.
- Determined that H2O metallizes above 6 TPa, lacking a stable low-temperature metallic form.
Conclusions:
- H2O exhibits complex phase behavior and decomposition pathways at TPa pressures.
- The predicted hydrogen-rich phase may influence the evolution of gas giant planets.
- New water ice structures offer insights into planetary interior compositions.
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