Effect of chainlike structures on shock-compressed liquid deuterium

We show that the presence of short chainlike structures in the dense fluid, modeled here for simplification as tetramers, can provide a mechanism to explain the surprisingly large compressibility of liquid deuterium observed in recent shock experiments at megabar pressures. The presence of chains leads to a large increase in the density of states and to a lowering of the Hugoniot temperature thereby increasing the compressibility that in turn increases the maximum density attained by the Hugoniot.