New Approximation for the Calculation of Neutron Scattering from a Simple Liquid

Abstract

A conceptually simple and easily applied approximation is made for the Van Hove distribution function $G(\mathbf{R},t)$ of a classical liquid. This approximation gives a less rapid temporal decay of $G(\mathbf{R},t)$ than is found in the Vinevard convolution approximation. In addition, by requiring that the sum rules be satisfied, we find that for $t$ smaller than about 0.5 × ${10}^{-13\mathrm{}}$ sec the "correlations" in a liquid may be said to be increasing. Comparisons are made with recent neutron scattering experiments. There is fair agreement between the theoretical and experimental results.