Dynamic heterogeneity and non-Gaussian behavior in a model supercooled liquid
نویسندگان
چکیده
We use a recently-derived reformulation of the diffusion constant [Stillinger F H and Debenedetti P G 2005 J. Phys. Chem. B 109 6604] to investigate heterogeneous dynamics and non-Gaussian diffusion in a binary LennardJones mixture. Our work focuses on the joint probability distribution of particles with velocity v0 at time t = 0 and eventual displacement ∆x at time t = ∆t. We show that this distribution attains a distinctive shape at the time of maximum nonGaussian behavior 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. Submitted to: J. Phys.: Condens. Matter PACS numbers: 61.20.Ja, 64.70.Pf, 66.10.Cb Dynamic heterogeneity and non-Gaussian behavior 2
منابع مشابه
Dynamic heterogeneity and non-Gaussian behaviour in a model supercooled liquid
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 v0 at time t = 0 and eventual displacement x at time t = t . We show that this distributi...
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