Frustrated ostwald ripening in self-assembled monolayers of cruciform pi-systems.

نویسندگان

  • Gina M Florio
  • Jennifer E Klare
  • Michelle O Pasamba
  • Tova L Werblowsky
  • Michelle Hyers
  • Bruce J Berne
  • Mark S Hybertsen
  • Colin Nuckolls
  • George W Flynn
چکیده

This study details a scanning tunneling microscopy investigation into the mechanism of chiral grain growth in highly ordered, self-assembled monolayer films composed of cruciform pi-systems. Although the molecules themselves are achiral, when they adsorb from solution onto graphite, they adopt a gear-like conformation that, by virtue of the surface, is chiral. These handed subunits arrange themselves into enantiomeric two-dimensional domains. The unique finding from this study is that Ostwald ripening is frustrated between domain boundaries that are of opposite chirality because direct interconversion between the chiral units on the surface is energetically inhibited.

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عنوان ژورنال:
  • Langmuir : the ACS journal of surfaces and colloids

دوره 22 24  شماره 

صفحات  -

تاریخ انتشار 2006