Mixtures of light elements with heavy elements are important in inertial confinement fusion. We explore the physics of molecular scale mixing through a validation study of equation of state (EOS) properties. Density functional theory molecular dynamics (DFT-MD) at elevated temperature and pressure is used to obtain the thermodynamic state properties of pure xenon, ethane, and various compressed mixture compositions along their principal Hugoniots. In order to validate these simulations, we have performed shock compression experiments using the Sandia Z-Machine. A bond tracking analysis correlates the sharp rise in the Hugoniot curve with the completion of dissociation in ethane. Furthermore, the DFT-based simulation results compare well with the experimental data along the principal Hugoniots and are used to provide insight into the dissociation and temperature along the Hugoniots as a function of mixture composition. Interestingly, we find that the compression ratio for complete dissociation is similar for several compositions suggesting a limiting compression for C-C bonded systems.
@article{osti_1235267,
author = {Magyar, Rudolph J. and Root, Seth and Mattsson, Thomas and Cochrane, Kyle Robert and Flicker, Dawn G.},
title = {Ethane-xenon mixtures under shock conditions},
annote = {Mixtures of light elements with heavy elements are important in inertial confinement fusion. We explore the physics of molecular scale mixing through a validation study of equation of state (EOS) properties. Density functional theory molecular dynamics (DFT-MD) at elevated temperature and pressure is used to obtain the thermodynamic state properties of pure xenon, ethane, and various compressed mixture compositions along their principal Hugoniots. In order to validate these simulations, we have performed shock compression experiments using the Sandia Z-Machine. A bond tracking analysis correlates the sharp rise in the Hugoniot curve with the completion of dissociation in ethane. Furthermore, the DFT-based simulation results compare well with the experimental data along the principal Hugoniots and are used to provide insight into the dissociation and temperature along the Hugoniots as a function of mixture composition. Interestingly, we find that the compression ratio for complete dissociation is similar for several compositions suggesting a limiting compression for C-C bonded systems.},
doi = {10.1103/PhysRevB.91.134109},
url = {https://www.osti.gov/biblio/1235267},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
issn = {ISSN 1098-0121},
number = {13},
volume = {91},
place = {United States},
publisher = {American Physical Society (APS)},
year = {2015},
month = {04}}
Cochrane, Kyle R.; Desjarlais, Michael; Mattsson, Thomas R.
SHOCK COMPRESSION OF CONDENSED MATTER - 2011: Proceedings of the Conference of the American Physical Society Topical Group on Shock Compression of Condensed Matter, AIP Conference Proceedingshttps://doi.org/10.1063/1.3686512