Volume 104, Number 1, October 2013
|Number of page(s)
|Interdisciplinary Physics and Related Areas of Science and Technology
|15 November 2013
On-off dissociation dynamics of colloidal doublets
1 Department of Chemistry and Molecular Biology, University of Gothenburg - SE-41296 Göteborg, Sweden
2 Department of Chemical Engineering, Chalmers University of Technology - SE-41296 Göteborg, Sweden
3 AstraZeneca R&D - SE-431 83 Mölndal, Sweden
Received: 12 August 2013
Accepted: 8 October 2013
First-passage time theory is used to analyze the dissociation behavior of doublets of colloidal particles. The first-passage time distribution for particles interacting via a DLVO potential is determined numerically. For strongly attractive particles the distribution becomes broad such that the mean first-passage time becomes a poor measure of the dynamics. In spite of this, use can be made of the mean in a matching condition, which allows for reproducing distributions for strongly attractive doublets by a semi-analytical solution for particles interacting only through surface adhesion. The smallest eigenvalue in the analytical solution, which governs the long-time asymptotic behavior of the first-passage time distribution, is identified analytically for strongly attractive pairs of particles. In addition, in this limit the distribution is shown to asymptote to an exponential distribution, which means that the dissociation process can be simply captured by an on-off model, without sacrificing the effect of the surface chemistry, with a constant probability for dissociation. This probability is simply related to the surface-adhesive parameter and the separation distance at which the pair of particles ceases to be considered a doublet.
PACS: 82.70.Dd – Colloids / 05.10.Gg – Stochastic analysis methods (Fokker-Planck, Langevin, etc.) / 05.40.Jc – Brownian motion
© EPLA, 2013
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.