Comments on the pressure dissociation of deuterium as related to the Nova laser Hugoniot

The recent Nova laser experimental Hugoniot for deuterium can be justified by a simple model which involves only very general properties of this mater ial and which highlights the role of the molecular dissociation. The region of maximal compression along the principal Hugoniot is characterized by rh o max/rhoo approximate to 8+4/2, T-max approximate to \E-B\ /2, P-max appro ximate to 3 rho (o) \E-B\, where E-B is the binding energy of a molecule, a nd rho (o) is the initial density.