2005/06/23 by M. Scott Shell, Pablo G. Debenedetti, Frank H. Stillinger · 1 citation
Chemical Engineering · Engineering · Materials Science · Physics and Astronomy · #Material Dynamics and Properties #Phase Equilibria and Thermodynamics #Thermodynamic properties of mixtures #cond-mat.soft
paper · pdf · doi:10.1088/0953-8984/17/49/002
published as J. Phys.: Condens. Matter 17, S4035 (2005). · 15 pages, 5 figures
arxiv created 2005/06/23 · openalex publication_date 2005/11/25 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/30
We use a recently derived reformulation of the diffusion constant (Stillinger and Debenedetti 2005 J. Phys. Chem. B 109 6604) to investigate heterogeneous dynamics and non-Gaussian diffusion in a binary Lennard-Jones mixture. Our work focuses on the joint probability distribution of particles with velocity v 0 at time t = 0 and eventual displacement Δ x at time t = Δ t . We show that this distribution attains a distinctive shape at the time of maximum non-Gaussian behaviour in the supercooled liquid. By performing a two-Gaussian fit of the displacement data, we obtain, in a non-arbitrary manner, two diffusive length scales inherent to the supercooled liquid and use them to identify spatially separated regions of mobile and immobile particles.