The origin of intermittent dynamics in the lattice gas modelF. M. Terraneo, P. Pinto and K. A. Dawson
School of Chemistry and Chemical Biology, University College Dublin - Belfield, Dublin 4, Ireland, EU
received 9 July 2008; accepted in final form 19 December 2008; published January 2009
published online 29 January 2009
The dilute lattice gas model is presented here as a paradigmatic illustration of the connection between subdiffusive behaviour, intermittency and the motion of available (empty) space. Applying a framework based on Continuous Time Random Walk theory, we are able to show how subdiffusive motion arises and how, and when, it crosses over to a diffusive regime. The relevant timescales, and , using arguments coming from simple principles are related to the (average) distance between vacant positions, . Quantities of interest, such as the mean square displacement and the number of movements, are predicted and compared to simulation results.
66.10.cg - Mass diffusion, including self-diffusion, mutual diffusion, tracer diffusion, etc.
05.40.Fb - Random walks and Levy flights.
64.70.P- - Glass transitions of specific systems.
© EPLA 2009