DOI: 10.1209/epl/i2003-00548-y
Europhys. Lett., 63 (3) , pp. 465-471 (2003)

Memory effects in correlated anisotropic diffusion

S. Fritzsche¹ and J. Kärger<sup>2

1</sup>  Leipzig University, Institute for Theoretical Physics Augustusplatz 9-11, D-04109 Leipzig, Germany
²  Leipzig University, Institute for Experimental Physics I Linnéstr. 5, D-04103 Leipzig, Germany

(Received 15 November 2002; accepted in final form 5 June 2003)

Abstract
Structure-related correlation of the principal values of the diffusion tensor is a unique feature of mass transfer in nanoporous crystalline solids. So far, analytical expressions of this correlation have been based on random-walk models with negligible memory effects. Considering crystals of type MFI for the first time the influence of memory effects on the correlated anisotropy of molecular diffusion is presented in a closed analytical expression. Comparison of the derived dependencies with the results of MD simulations yields satisfactory agreement.

PACS
83.10.Mj - Molecular dynamics, Brownian dynamics.
31.15.Qg - Molecular dynamics and other numerical methods.
82.75.Jn - Measurements and modeling of molecule migration in zeolites.

© EDP Sciences 2003