  We have performed accurate simulations of the Deuterium Hugoniot using
Coupled Electron Ion Monte Carlo (CEIMC). Using highly accurate quantum Monte
Carlo methods for the electrons, we study the region of maximum compression
along the principal Hugoniot, where the system undergoes a continuous
transition from a molecular fluid to a monatomic fluid. We include all relevant
physical corrections so that a direct comparison to experiment can be made.
Around 50 GPa we found a maximum compression of 4.85, roughly 10% larger than
previous theoretical predictions and experimental data but still compatible
with the latter because of their large uncertainty.
