Density-functional calculation of the Hugoniot of shocked liquid deuterium

We have performed molecular dynamics simulations to obtain the internal energy and pressure of shock-compressed fluid deuterium at 24 separate (density temperature) points. Our calculations were performed using the generalized gradient approximation (GGA) in density-functional theory. We obtained a good fit to this simulation data with a thermodynamically consistent virial expansion. The single-shock Hugoniot derived from this equation of state is compared to previous theoretical and experimental results. We discuss several types of error inherent in the GGA, as they relate to the quality of our results.