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Methane Hydrate Crystallization on Sessile Water Droplets
Published on: May 26, 2021
On the structure selectivity of clathrate hydrates
Masakazu Matsumoto1, Hideki Tanaka
1Graduate School of Natural Science and Technology, Okayama University, Tsushima, Okayama, Japan. vitroid@gmail.com
The Journal of Physical Chemistry. B
|May 31, 2011
Summary
Researchers developed a new method to find novel clathrate hydrates by analyzing crystalline structure selectivity. This approach predicts hydrate stability based on guest molecules and thermodynamic conditions, aiding in the discovery of new clathrate structures.
Area of Science:
- Materials Science
- Chemical Physics
- Crystallography
Background:
- Clathrate hydrate structure selectivity is primarily attributed to guest species, with less influence from thermodynamic conditions.
- Understanding clathrate hydrate polymorphism is crucial for predicting and discovering new crystalline structures.
Purpose of the Study:
- To propose a strategic method for discovering new clathrate hydrates.
- To investigate the selectivity of clathrate hydrate crystalline structures.
- To explain the stability of major clathrate hydrate structures and their relationship with guest properties.
Main Methods:
- Examining the relative stability of clathrate hydrate morphologies using the chemical potential of water.
- Calculating the free energy of cage occupancy via standard statistical mechanical theory.
- Employing Yarmolyuk and Kripyakevich's rule for Frank-Kasper type alloys to estimate cage types.
Main Results:
- A comprehensive interpretation of clathrate hydrate crystalline structure selectivity was achieved.
- The study explains the stability of two major clathrate hydrate structures across various thermodynamic conditions.
- A relationship between clathrate hydrate polymorphism, guest size, and other parameters was established, indicating potential for new structures.
Conclusions:
- The proposed method provides a pathway to discover new clathrate hydrates by selecting appropriate guest species and thermodynamic conditions.
- A small parameter space exists for less common clathrate hydrate structures, including novel ones, to become the most stable.
- The preferential formation of the TS-I structure in bromine hydrate was elucidated.
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