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Title: Non-Gaussian nature of glassy dynamics by cage to cage motion

Abstract

A model based on a single Brownian particle moving in a periodic effective field is used to understand the non-Gaussian dynamics in glassy systems of cage escape and subsequent recaging, often thought to be caused by a heterogeneous glass structure. The results are compared to molecular-dynamics simulations of systems with varying complexity: quasi-two-dimensional colloidlike particles, atactic polystyrene, and a dendritic glass. The model nicely describes generic features of all three topologically different systems, in particular around the maximum of the non-Gaussian parameter. This maximum is a measure for the average distance between cages.

Authors:
; ;  [1];  [2]
  1. Group Polymer Physics, Eindhoven Polymer Laboratories and Dutch Polymer Institute, Technische Universiteit Eindhoven, P.O. Box 513, 5600 MB Eindhoven (Netherlands)
  2. Chemical Engineering Department, Aristotle Univerisity of Thessaloniki, 54124 Thessaloniki (Greece)
Publication Date:
OSTI Identifier:
21072272
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics; Journal Volume: 75; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevE.75.011504; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BROWNIAN MOVEMENT; COLLOIDS; COMPUTERIZED SIMULATION; DENDRITES; GLASS; MOLECULAR DYNAMICS METHOD; PERIODICITY; POLYSTYRENE

Citation Formats

Vorselaars, Bart, Lyulin, Alexey V., Michels, M. A. J., and Karatasos, K. Non-Gaussian nature of glassy dynamics by cage to cage motion. United States: N. p., 2007. Web. doi:10.1103/PHYSREVE.75.011504.
Vorselaars, Bart, Lyulin, Alexey V., Michels, M. A. J., & Karatasos, K. Non-Gaussian nature of glassy dynamics by cage to cage motion. United States. doi:10.1103/PHYSREVE.75.011504.
Vorselaars, Bart, Lyulin, Alexey V., Michels, M. A. J., and Karatasos, K. Mon . "Non-Gaussian nature of glassy dynamics by cage to cage motion". United States. doi:10.1103/PHYSREVE.75.011504.
@article{osti_21072272,
title = {Non-Gaussian nature of glassy dynamics by cage to cage motion},
author = {Vorselaars, Bart and Lyulin, Alexey V. and Michels, M. A. J. and Karatasos, K.},
abstractNote = {A model based on a single Brownian particle moving in a periodic effective field is used to understand the non-Gaussian dynamics in glassy systems of cage escape and subsequent recaging, often thought to be caused by a heterogeneous glass structure. The results are compared to molecular-dynamics simulations of systems with varying complexity: quasi-two-dimensional colloidlike particles, atactic polystyrene, and a dendritic glass. The model nicely describes generic features of all three topologically different systems, in particular around the maximum of the non-Gaussian parameter. This maximum is a measure for the average distance between cages.},
doi = {10.1103/PHYSREVE.75.011504},
journal = {Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics},
number = 1,
volume = 75,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}
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