Document Type
Article
Publication Date
6-25-2010
Abstract
A substrate coated with an achiral polyimide alignment layer was scribed bidirectionally with the stylus of an atomic force microscope to create an easy axis for liquid crystal orientation. The resulting noncentrosymmetric topography resulted in a chiral surface that manifests itself at the molecular level. To show this unambiguously, a planar-aligned negative dielectric aniostropy achiral nematic liquid crystal was placed in contact with the surface and subjected to an electric field E. The nematic director was found to undergo an azimuthal rotation approximately linear in E. This so-called "surface electroclinic effect" is a signature of surface chirality and was not observed when the polyimide was treated for a centrosymmetric topography, and therefore was nonchiral.
Keywords
azimuthal rotation, centrosymmetric, chiral surface, easy axis, electroclinic effect, molecular levels, nano scale, negative dielectric, nematic director, non-centrosymmetric, polyimide alignment layers, surface chirality, chirality, electric fields, enantiomers, liquid crystals, liquids, nematic liquid crystals, polyimides, single crystals, stereochemistry, surface topography, crystal orientation, atomic force microscopes
Publication Title
Physical Review Letters
Rights
© 2010 The American Physical Society.
Recommended Citation
Mechanically Generated Surface Chirality at the Nanoscale. Ferjani S., Choi Y., Pendery J., Petschek R.G., Rosenblatt C., Physical Review Letters 104:25, 2010.