Molecular-dynamics study of the dynamical structure factor of liquidN2

Abstract

The equilibrium and dynamical structure factors of a nitrogenlike system near its triple point are computed by a molecular-dynamics simulation using an "atom-atom" potential. Both structure factors are shown to be almost identical to the structure factors of a system of spherical molecules when the intramolecular contributions have been subtracted and the rotational degrees of freedom taken into account in a trivial way. Thus only very little information on the anisotropic part of the intermolecular interaction can be gained from these two quantities. For the dynamical structure factor, a strong and unexpected disagreement between our computation and the experiment of Carneiro and McTague at small wave numbers probably indicates that the experimental results should be corrected for double-scattering contributions.