Molecular-dynamics study of the dependence of self-diffusion on system size in a dense binary liquid of hard spheres

Josef Jäckle and Hidetoshi Kawai

Physica A: Statistical Mechanics and its Applications, 2001, vol. 291, issue 1, 184-196

Abstract: The dependence on system size of self-diffusion in a dense binary liquid of hard spheres was studied by molecular dynamics simulation of two systems with 216 and 5832 particles. The ratio of particle radii is α=0.85. The relative difference between the self-diffusion coefficients Ds for both system sizes increases from 11% to 18% as the packing fraction φ is increased from 0.533 to 0.563. The relation between the size dependence of Ds and the underlying size dependence of the velocity-autocorrelation function (VAF) was studied in detail for φ=0.548. For intermediate and long times the difference Δψ(t) of the VAFs for the two sizes is well reproduced by the mode-coupling formula expressing the coupling of self-diffusion to modes of collective flow. However, the short-time part of Δψ(t) is equally important. A simpler relation was found between the size dependence of Ds and that of the memory function M(t) associated with the VAF. M(t) is larger and decays more slowly for the smaller systems, which leads to the observed size dependence of Ds.

Date: 2001
References: View complete reference list from CitEc
Citations:

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0378437100004817
Full text for ScienceDirect subscribers only. Journal offers the option of making the article available online on Science direct for a fee of $3,000

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:phsmap:v:291:y:2001:i:1:p:184-196

DOI: 10.1016/S0378-4371(00)00481-7

Access Statistics for this article

Physica A: Statistical Mechanics and its Applications is currently edited by K. A. Dawson, J. O. Indekeu, H.E. Stanley and C. Tsallis

More articles in Physica A: Statistical Mechanics and its Applications from Elsevier
Bibliographic data for series maintained by Catherine Liu ().