Repulsion by Attraction and Attraction by Repulsion

by Uri Sivan

at Physics Colloquium

Thu, 10 Mar 2016, 15:30
Physics building (#54) room 207

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 most important aspect namely the nature of the short range force or even its sign has never been resolved Using an ultra high resolution AFM built in house we finally succeeded in measuring the interaction at all distances and found unexpectedly that the short range interaction is repulsive rather than attractive In the talk I will present the atomic force microscope 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 aqueous solutions Refreshments are served at 3:20pm

Created on 01-03-2016 by Bar Lev, Yevgeny (ybarlev)
Updaded on 01-03-2016 by Bar Lev, Yevgeny (ybarlev)