Properties of Carbon under High Pressure-Temperature Conditions inside the Cores of Rocky Exoplanets
Abstract
Cores of recently discovered Super-Earth rocky exoplanets experience extremely high pressures in terapascal range and temperatures up to 10 kK. Their interiors might contain solid and liquid phases of carbon as in carbon-rich 55 Cancri e Super-Earth. Therefore, understanding the behavior of carbon at extreme pressures and temperatures is urgently sought for the development of interior models of the diverse class of rocky exoplanets. The phase diagram of carbon at extreme pressures and temperatures relevant to the core conditions of exoplanets is investigated using first-principles density functional theory and quantum accurate Spectral Neighbor Analysis Potential (SNAP) molecular dynamics. Melt-line and diamond/bc8/liquid triple point are calculated and compared with previous computations and experiments. Full thermodynamic description solid and liquid phases of carbon at pressures and temperatures obtained in this work will allow more precise constrains on mass-radius relationships of carbon-rich exoplanets.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFMMR22A..06B
- Keywords:
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- 3919 Equations of state;
- MINERAL PHYSICS;
- 3924 High-pressure behavior;
- MINERAL PHYSICS;
- 3939 Physical thermodynamics;
- MINERAL PHYSICS;
- 3994 Instruments and techniques;
- MINERAL PHYSICS