Long-time self-diffusion for Brownian Gaussian-core particles

Using extensive Brownian dynamics computer simulations, the long-time self-diffusion coefficient is calculated for Gaussian-core particles as a function of the number density. Both spherical and rod-like particles interacting via Gaussian segments are considered. For increasing concentration we find that the translational self-diffusion behaves non-monotonically reflecting the structural reentrance effect in the equilibrium phase diagram. Both in the limits of zero and infinite concentration, it approaches its short-time value. The microscopic Medina-Noyola theory qualitatively accounts for the translational long-time diffusion. The long-time orientational diffusion coefficient for Gaussian rods, on the other hand, remains very close to its short-time counterpart for any density. Some implications of the weak translation

• Type: Journal
• Year: 2008
• Where: CPHYSICS
• Authors: H. H. Wensink, H. Löwen, M. Rex, C. N. Likos, S. van Teeffelen
• Keywords: CPHYSICS 2008, Extensive Brownian Dynamics, Long-time Orientational Diffusion, Translational Long-time Diffusion