Jump to main content
Jump to site search

Issue 9, 2011
Previous Article Next Article

Effective interactions and equilibrium configurations of colloidal particles on a sessile droplet

Author affiliations

Abstract

We study the free energy landscapes of a pair of micron-sized spherical particles floating at the surface of a sessile droplet. The particles are subjected to radial external forces resulting in a deformation of the droplet shape relative to the reference shape of a spherical cap. This deformation leads to tangential forces on the particles. For small deformations and for the contact angle θ0 at the substrate being equal to π/2, the corresponding linearized Young-Laplace equation is solved analytically. The solution is constructed by employing the method of images from electrostatics, where each of the particles plays the role of a capillary monopole and the substrate is replaced by a virtual drop with image charges and by imposing the conditions of fixed droplet volume and vanishing total force on the droplet. The substrate boundary conditions determine the signs of the image capillary charges and therefore also the strength of the tangential forces on the particles. In the cases of an arbitrary contact angle θ0 these forces are calculated numerically by employing a finite element method to find the equilibrium shape of the droplet for those configurations in which the particles are close to the local free energy minima.

Graphical abstract: Effective interactions and equilibrium configurations of colloidal particles on a sessile droplet

Back to tab navigation

Publication details

The article was received on 07 Dec 2010, accepted on 02 Feb 2011 and first published on 09 Mar 2011


Article type: Paper
DOI: 10.1039/C0SM01440K
Citation: Soft Matter, 2011,7, 4189-4197
  •   Request permissions

    Effective interactions and equilibrium configurations of colloidal particles on a sessile droplet

    J. Guzowski, M. Tasinkevych and S. Dietrich, Soft Matter, 2011, 7, 4189
    DOI: 10.1039/C0SM01440K

Search articles by author

Spotlight

Advertisements