Dissociation of Methane into Hydrocarbons at Extreme (Planetary) Pressure and Temperature
- 28 February 1997
- journal article
- other
- Published by American Association for the Advancement of Science (AAAS) in Science
- Vol. 275 (5304) , 1288-1290
- https://doi.org/10.1126/science.275.5304.1288
Abstract
Constant-pressure, first-principles molecular dynamic simulations were used to investigate the behavior of methane at high pressure and temperature. Contrary to the current interpretation of shock-wave experiments, the simulations suggest that, below 100 gigapascals, methane dissociates into a mixture of hydrocarbons, and it separates into hydrogen and carbon only above 300 gigapascals. The simulation conditions (100 to 300 gigapascals; 4000 to 5000 kelvin) were chosen to follow the isentrope in the middle ice layers of Neptune and Uranus. Implications on the physics of these planets are discussed.Keywords
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