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Updated: Apr 1, 2026

Measuring the Interaction Force Between a Droplet and a Super-hydrophobic Substrate by the Optical Lever Method
Published on: June 14, 2019
The Influence of Long-Range Surface Forces on the Contact Angle of Nanometric Droplets and Bubbles
Antonio Stocco1,2, Helmuth Möhwald3
1Laboratoire Charles Coulomb (L2C), UMR 5221 CNRS-University of Montpellier , Montpellier F-34095, France.
Abstract:
For a droplet or a bubble of dimensions below 100 nm, long-range surface forces such as long-range van der Waals forces can compete with capillarity, which leads to a size dependence of the contact angle. This is discussed in this work, where we also show that the effect cannot simply be described by a normalized line tension. We calculate interfacial profiles for typical values of van der Waals forces and discuss the role of long-range surface forces on the contact angle of nanobubbles and nanodrops.
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