Visualization of the cholesteric texture near a Grandjean line

Abstract

The twisted structure near a Grandjean line in a cholesterically ordered liquid crystalline network is visualized by scanning electron microscopy. It is shown that the formation of an extra π-rotation in the molecular helix at a Grandjean line occurs at a localized depth in the sample and gives rise to an edge dislocation of strength 1/2, dissociated into a pair of two simple line dislocations.