Home

About

Advanced Search

Browse by Discipline

Scientific Societies

E-print Alerts

Add E-prints

E-print Network
FAQHELPSITE MAPCONTACT US


  Advanced Search  

 
Orientational Order of Molecular Assemblies on Rough Surfaces Hannes C. Schniepp, Ho C. Shum, Dudley A. Saville, and Ilhan A. Aksay*
 

Summary: Orientational Order of Molecular Assemblies on Rough Surfaces
Hannes C. Schniepp, Ho C. Shum, Dudley A. Saville, and Ilhan A. Aksay*
Department of Chemical Engineering, Princeton UniVersity, Princeton, New Jersey 08544
ReceiVed: April 29, 2008
Using atomic force microscopy, we show that previous observations on the orientational order of micelles on
atomically smooth crystals with directions dictated by the crystal symmetry is only valid for the case of
perfectly smooth crystals. On rough surfaces, orientations are independent of the lattice symmetry and the
observed directions can be explained by considering the guiding influence of topographic surface features.
Introduction
Surfactant aggregates exhibit strong, lattice-induced orien-
tational order on a number of atomically smooth, crystalline
substrates.1-4 There have been several earlier attempts to
rationalize this order. Manne and Gaub suspected a crystalline
anisotropy in the van der Waals interactions as its origin.2
Wanless and Ducker, in contrast, suggested that all observed
orientational order is induced by topographic steps.5 The latter
view is not in agreement with a substantial amount of the
reported experimental evidence: the great majority of surfactant
micelles on highly oriented pyrolytic graphite (HOPG) surfaces
run perpendicularly with respect to the lattice symmetry axes,1,4

  

Source: Aksay, Ilhan A. - Department of Chemical Engineering, Princeton University

 

Collections: Materials Science