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Updated: Jun 4, 2026
08:46
Methane Hydrate Crystallization on Sessile Water Droplets
Published on: May 26, 2021
Structural, electronic, and dynamical properties of methane under high pressure
1Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, People's Republic of China.
The Journal of Chemical Physics
|February 17, 2011
Summary
High-pressure studies reveal solid methane
Area of Science:
- Solid-state physics
- Materials science
- Computational chemistry
Background:
- Understanding methane's behavior under extreme conditions is crucial for planetary science.
- Previous studies have indicated complex phase transitions in solid methane at high pressures.
Purpose of the Study:
- To investigate the electronic structure and lattice dynamics of solid methane under high pressure.
- To identify structural phase transitions and their properties.
Main Methods:
- Density functional theory (DFT) calculations were employed.
- Analysis of electronic band structure and phonon spectra.
Main Results:
- Identified distinct crystal structures and phase transitions at specific pressure ranges (e.g., I43m, Pmn2(1), P2(1)/c, Pnma).
- Calculated Raman spectra for the P2(1)/c phase show good agreement with experimental data.
- Methane remains insulating and molecular across all studied pressures.
- Observed changes in orientational ordering and molecular freezing in the Pnma phase at higher pressures.
Conclusions:
- Solid methane exhibits complex structural transformations under high pressure.
- DFT provides accurate predictions for methane's high-pressure phases and properties.
- Methane retains its molecular and insulating nature even at extreme pressures.
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