We study the dynamics of monodisperse hard ellipsoids via a new event-driven molecular dynamics algorithm as a function of volume fraction phi and aspect ratio X-0. We evaluate the translational D-trans and the rotational D-rot diffusion coefficients and the associated isodiffusivity lines in the phi-X-0 plane. We observe a decoupling of the translational and rotational dynamics which generates an almost perpendicular crossing of the D-trans and D-rot isodiffusivity lines. While the self-intermediate scattering function exhibits stretched relaxation, i.e., glassy dynamics, only for large phi and X-0 approximate to 1, the second order orientational correlator C-2(t) shows stretching only for large and small X-0 values. We discuss these findings in the context of a possible prenematic order driven glass transition.
Dynamics of uniaxial hard ellipsoids / DE MICHELE, Cristiano; Schilling, R; Sciortino, Francesco. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - STAMPA. - 98:(2007), pp. 265702-1-265702-4. [10.1103/PhysRevLett.98.265702]
Dynamics of uniaxial hard ellipsoids
DE MICHELE, CRISTIANO;SCIORTINO, Francesco
2007
Abstract
We study the dynamics of monodisperse hard ellipsoids via a new event-driven molecular dynamics algorithm as a function of volume fraction phi and aspect ratio X-0. We evaluate the translational D-trans and the rotational D-rot diffusion coefficients and the associated isodiffusivity lines in the phi-X-0 plane. We observe a decoupling of the translational and rotational dynamics which generates an almost perpendicular crossing of the D-trans and D-rot isodiffusivity lines. While the self-intermediate scattering function exhibits stretched relaxation, i.e., glassy dynamics, only for large phi and X-0 approximate to 1, the second order orientational correlator C-2(t) shows stretching only for large and small X-0 values. We discuss these findings in the context of a possible prenematic order driven glass transition.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.