Our paper on hydrocarbons published in Phys. Rev. E!

The shock Hugoniot curve of CH across gigabar pressures.


Using new quantum mechanical methods, we were able to predict the behavior of hydrocarbons across gigabar pressures, conditions that correspond to the deep interiors of stars, more accurately than previous models. These interior-like conditions are currently being probed at the National Ignition Facility for developments in internal confinement fusion (ICF) and astrophysics. Warm, dense hydrocarbons are of broad interests to the scientific community because they are relevant to evolved massive stars and because of their use as standard ablator materials which initiate the laser shock in dynamic compression and ICF experiments. An accurate understanding of their equation of state (EOS), shock compression, and mixing properties is critical to related scientific missions. For our calculation, we used first-principles methods to thoroughly characterize a series of hydrocarbons from the electronic level. By well accounting the physics of electronic shell effects and many-body interactions we were able to produce a significantly improved EOS beyond previous semi-empirical models. In addition, the work is the first in completely probing the effects of mixing in the high temperature regime where the system still undergoes partial ionization. Our results provide a benchmark for other theoretical methods and deeper insight into the interpretation of gigabar experiments coming online.


Read the whole articles here:
Shuai Zhang, Kevin P. Driver, Francois Soubiran, Burkhard Militzer, "First-principles Equation of State and Shock Compression Predictions of Warm Dense Hydrocarbons", Phys. Rev. E 96, 013204 (2017). (also see arXiv: physics.plasm-ph).

2017-07-10