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Updated: Sep 20, 2025
08:46
Methane Hydrate Crystallization on Sessile Water Droplets
Published on: May 26, 2021
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Formation and Stability of Dense Methane-Hydrogen Compounds
Umbertoluca Ranieri1,2, Lewis J Conway3, Mary-Ellen Donnelly1
1Center for High Pressure Science and Technology Advanced Research, 1690 Cailun Road, Shanghai, 201203, China.
Physical Review Letters
|June 10, 2022
Summary
Researchers discovered new methane-hydrogen compounds at high pressures. These structures, stabilized by quantum effects, hold over 50% hydrogen, advancing materials science.
Area of Science:
- Materials Science
- High-Pressure Physics
- Quantum Chemistry
Background:
- Understanding the behavior of molecular systems under extreme pressure is crucial for fields like planetary science and materials discovery.
- Methane (CH4) and hydrogen (H2) mixtures are relevant to dense planetary interiors.
Purpose of the Study:
- To investigate the structural and vibrational properties of dense methane-hydrogen systems.
- To identify novel compounds formed under high pressure and explore their hydrogen content.
Main Methods:
- X-ray diffraction
- Optical spectroscopy using diamond anvil cells
- Density functional theory (DFT) calculations
Main Results:
- Stabilization of CH4(H2)2 and (CH4)2H2 at pressures as low as 4.8 GPa.
- Observation of significant hardening of H2 intramolecular vibrations in (CH4)2H2.
- Discovery of a novel (CH4)3(H2)25 structure exceeding 50 wt% H2.
- These compounds are stabilized by nuclear quantum effects and persist up to 160 GPa.
Conclusions:
- Novel methane-hydrogen compounds with exceptionally high hydrogen content have been synthesized.
- Nuclear quantum effects play a critical role in stabilizing these unique high-pressure phases.
- The findings open new avenues for designing hydrogen-rich materials.
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