Spontaneous Formation of Macroscopic Chiral Domains in a Fluid Smectic Phase of Achiral Molecules

• DOI: 10.1126/science.278.5345.1924
• Publication Date: 2002-07-27T09:45:15Z
• Authors: Darren R. Link; Giorgio Natale; Renfan Shao; Joseph E. Maclennan; Noel A. Clark; Eva Körblova; David M. Walba
• Keywords: 02 engineering and technology; 0210 nano-technology

A smectic liquid-crystal phase made from achiral molecules with bent cores was found to have fluid layers that exhibit two spontaneous symmetry-breaking instabilities: polar molecular orientational ordering about the layer normal and molecular tilt. These instabilities combine to form a chiral layer structure with a handedness that depends on the sign of the tilt. The bulk states are either antiferroelectric-racemic, with the layer polar direction and handedness alternating in sign from layer to layer, or antiferroelectric-chiral, which is of uniform layer handedness. Both states exhibit an electric field–induced transition from antiferroelectric to ferroelectric.