Abstract
We present a general derivation of the non-Fickian behavior for the self-diffusion of identically interacting particle systems with excluded mutual passage. We show that the conditional probability distribution of finding a particle at position after time , when the particle was located at at , follows a Gaussian distribution in the long-time limit, with variance for overdamped systems and with variance for classical systems. The asymptotic behavior of the mean-squared displacement, , is shown to be independent of the nature of interactions for homogeneous systems in the fluid state. Moreover, the long-time behavior of self-diffusion is determined by short-time and large-scale collective density fluctuations.
- Received 22 November 2002
DOI:https://doi.org/10.1103/PhysRevLett.90.180602
©2003 American Physical Society