Physics (Internal)

Long-time diffusion of polydisperse hard disks and hard spheres

This event is part of the Collider Search Candidate Seminars.

Abstract: The long-time diffusion process of hard disks is compared with that of hard spheres by performing extensive event-driven molecular simulations. The volume fraction dependence of the mean-square displacements, and the self-intermediate scattering function of both systems are fully investigated. The singular function, which has been proposed by Tokuyama, is found to describe the long-time self-diffusion coefficient of both hard disks and hard spheres from liquid state to supercooled liquid state. The characteristic times of the beta relaxation process and the alpha relaxation process of hard disks are also found to be similar to those of hard spheres when the particles had the same long-time self-diffusion coefficient. The spatial dimension d changes the value of the glass transition point and peak height of the non-Gaussian parameter which are related to the geometric packing characteristics of hard disks and hard spheres.