https://doi.org/10.1140/epje/i2007-10314-1
ISMC-2007
Ellipsoidal particles at fluid interfaces
1
Max-Planck-Institut für Metallforschung, Heisenbergstr. 3, D-70569, Stuttgart, Germany
2
Institut für Theoretische und Angewandte Physik, Universität Stuttgart, Pfaffenwaldring 57, D-70569, Stuttgart, Germany
3
Institut für Physik, WA 331, Johannes-Gutenberg-Universität Mainz, D-55099, Mainz, Germany
* e-mail: oettelm@uni-mainz.de
Received:
20
September
2007
Accepted:
17
March
2008
Published online:
2
May
2008
For partially wetting, ellipsoidal colloids trapped at a fluid interface, their effective, interface-mediated interactions of capillary and fluctuation-induced type are analyzed. For contact angles different from 90° , static interface deformations arise which lead to anisotropic capillary forces that are substantial already for micrometer-sized particles. The capillary problem is solved using an efficient perturbative treatment which allows a fast determination of the capillary interaction for all distances between and orientations of two particles. Besides static capillary forces, fluctuation-induced forces caused by thermally excited capillary waves arise at fluid interfaces. For the specific choice of a spatially fixed three-phase contact line, the asymptotic behavior of the fluctuation-induced force is determined analytically for both the close-distance and the long-distance regime and compared to numerical solutions.
PACS: 82.70.Dd Colloids – / 68.03.Cd Surface tension and related phenomena – / 05.40.-a Fluctuation phenomena, random processes, noise, and Brownian motion –
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag, 2008