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Molecular Correlation Functions for Uniaxial Ellipsoids in the Isotropic State

Cristiano De Michele·Antonio Scala·Rolf Schilling·Francesco Sciortino
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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.

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Cristiano De Michele, Antonio Scala, Rolf Schilling, Francesco Sciortino. 2005-11-04. Molecular Correlation Functions for Uniaxial Ellipsoids in the Isotropic State. https://doi.org/10.1063/1.2176679

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