An Inversion of Chirality at a Chiral Micelle Surface

Abstract

Two chiral quaternary ammonium bromide detergents S-1,2- and S-2,1-N-hexadecyl-N,N-dimethyl propanol bromide with the same S molecular configuration which are constituent isomers have been synthesised. They were used to prepare Amphiphillic Cholesteric Liquid Crrstal (ACLC) samples where the molecular stereochemistry in respect to the micelle surface was inverted in respect to one another. Concomitant inversions in the sign of the optical rotation were found using the polarising microscope. Laser diffraction was used to determine the twists in these ACLC samples, which were found to be exceptionally small. The small twists were thought to be the result of the hydroxyl group in the chiral amphiphillic head group pushing the chiral centres apart.

Key Words:

• Amphiphilic liquid crystal
• chiral micelle surface
• cholesteric liquid crystal