Dynamic structure of dense krypton gas

Abstract

We have made molecular-dynamics computer simulations of dense krypton gas ($10.6\ifmmode\times\else\texttimes\fi{}{10}^{27}$ atoms/${\mathrm{m}}^{3}$ and 296 K) using reasonably realistic pair potentials. Comparisons are made with the recent experimental data[P. A. Egelstaff et al., Phys. Rev. A 27, 1106 (1983)] for the dynamic structure factor $S(q,\ensuremath{\omega})$ over the range $0.4<q<3.0$ ${\mathrm{\AA{}}}^{\ensuremath{-}1}$. For $q<1.6$ ${\mathrm{\AA{}}}^{\ensuremath{-}1}$ the influence of the attractive part of the potential is important and shorter-ranged many-body forces are found to play a role. Additional (less significant on a relative scale) effects are found in the region $q~2.7$ ${\mathrm{\AA{}}}^{\ensuremath{-}1}$. Some suggestions for future work are made.