Molecular Correlation Functions for Uniaxial Ellipsoids in the Isotropic State

TL;DR

This study uses molecular dynamics simulations to analyze uniaxial ellipsoids, comparing theoretical and numerical structure factors, revealing shape-sensitive orientational properties and validating theoretical approximations.

Contribution

It provides a detailed comparison between Percus-Yevick theoretical predictions and simulation results for uniaxial ellipsoids, highlighting shape-dependent orientational features.

Findings

Theoretical and numerical structure factors agree satisfactorily.

Molecular structure factors can distinguish prolate from oblate ellipsoids.

First-order shape expansion explains shape sensitivity in orientational quantities.

Abstract

We perform event-driven molecular dynamics simulations of a system composed by uniaxial hard ellipsoids for different values of the aspect-ratio and packing fraction . We compare the molecular orientational-dependent structure factors previously calculated within the Percus-Yevick approximation with the numerical results. The agreement between theoretical and numerical results is rather satisfactory. We also show that, for specific orientational quantities, the molecular structure factors are sensitive to the particle shape and can be used to distinguish prolate from oblate ellipsoids. A first-order theoretical expansion around the spherical shape and a geometrical analysis of the configurations confirms and explains such an observation.