Lecturer: Prof. Uri Sivan
Affiliation: Department of Physics
and the Russell Berrie Nanotechnology Institute
Technion - Israel Institute of Technology
Abstract:
The interface between water and
hydrophobic surfaces is ubiquitous in
nature and technology and so is the water
mediated interaction between hydrophobic
objects. Decades long efforts have been
invested in deciphering the mechanism
underlying the hydrophobic force but this
quest has proved more elusive than
anticipated. In particular, the nature of the
short-range force, or even its sign, have
never been resolved.
Using a new ultra-high resolution atomic
force microscope built in-house, we
recently succeeded in measuring this
interaction and found that contrary to the
accepted dogma the short range interaction
is repulsive rather than attractive. This
finding has far reaching consequences for
dozens of phenomena.
In the talk I will present the instrument that
served us, the experimental results, and a
theory that yields such repulsion. The
theory will link the hydrophobic interaction
to another long standing puzzle in physical
chemistry of water.