We use molecular dynamics (MD) to study the kinetics of surface enrichment (SE) in a stable homogeneous mixture (AB), placed in contact with a surface which preferentially attracts A. The SE profiles show a characteristic double-exponential behavior with two length scales: \xi_-, which rapidly saturates to its equilibrium value, and \xi_+, which diverges as a power-law with time (\xi_+ \sim t^\theta). We find that hydrodynamic effects result in a crossover of the growth exponent from \theta \simeq 0.5 to \theta \simeq 1.0. There is also a corresponding crossover in the growth dynamics of the SE-layer thickness.
@article{arxiv.1011.6290,
title = {Kinetics of Surface Enrichment: A Molecular Dynamics Study},
author = {Prabhat K. Jaiswal and Sanjay Puri and Subir K. Das},
journal= {arXiv preprint arXiv:1011.6290},
year = {2010}
}
Comments
20 pages, 6 figures, Published in J. Chem. Phys. (Research Highlights)