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Updated: Dec 30, 2025
08:46
Methane Hydrate Crystallization on Sessile Water Droplets
Published on: May 26, 2021
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How methane hydrate recovers at very high pressure the hexagonal ice structure.
S Schaack1, Ph Depondt1, M Moog2
1Sorbonne Université, Institut des Nanosciences de Paris (INSP), CNRS UMR 7588, Paris, France.
The Journal of Chemical Physics
|January 17, 2020
Summary
High-pressure methane hydrate (MH) phases (MH-III and MH-IV) were studied. Quantum effects significantly influence the phase transition mechanism involving hydrogen bonds and methane reordering.
Area of Science:
- Geochemistry
- Materials Science
- Physical Chemistry
Background:
- Methane hydrate is stable up to 150 GPa.
- A new high-pressure phase (MH-IV) exists above 40 GPa.
- Understanding phase stability is crucial for high-pressure applications.
Purpose of the Study:
- To investigate the relative stability of methane hydrate phases MH-III and MH-IV.
- To analyze the mechanism of the phase transition between MH-III and MH-IV.
- To elucidate the role of nuclear quantum effects in this transition.
Main Methods:
- Metadynamics simulations.
- Path integral molecular dynamics.
- Analysis of hydrogen bond dynamics and methane reordering.
Main Results:
- The phase transition involves hydrogen bond breaking and reforming.
- Methane molecules undergo reordering during the transition.
- Nuclear quantum effects, specifically hydrogen nuclear delocalization, play a significant role.
Conclusions:
- The transition pathway between MH-III and MH-IV is complex.
- Quantum effects are critical for accurately describing methane hydrate behavior at high pressures.
- This research provides insights into the fundamental properties of matter under extreme conditions.
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