Long-Range Attractive Force Between Hydrophobic Surfaces Observed by Atomic Force Microscopy

There is evidence from atomic force microscopy for a long-range attractive force between hydrophobic surfaces that is virtually identical to that observed with the surface forces apparatus. This force is present in the nonaqueous solvent ethylene glycol. A possible molecular mechanism involves in-plane polarized domains of solid-like monolayers adsorbed on mica, and a theoretical model has been developed that accounts for many of the observations.