Large scale calculations of the structure and dynamics of dense matter

The physics of matter at high density has been found to be strongly influenced by transient quasi-molecular phenomena, the distribution of electron charge density among several nearby atoms. Calculations performed using the self-consistent field molecular dynamics approximation, a synthesis of techniques derived from quantum chemistry and molecular dynamics, have shown that such effects can result in more than a 30% increase in the diffusion coefficient of helium at 1 g/cc. The effect of finite electron temperature is to weaken many-electron collective phenomena, but significant effects are expected to occur even in fully ionized dense plasmas. 10 refs., 6 figs