Pitch and Sense of Helix in Mixtures of Optically Active Azo or Azoxy Compounds and Nematic Liquid Crystal

Abstract

Mixtures of azo or azoxy compound with asymmetric side chains and a nematic liquid crystal, and the pitch and sense of the helix were examined. Compounds with two identical optically active side chains exhibited the twisting power twice that of compounds with one optically active side chain. As a result, it was found that a feature value (M/Pc), where M, P and c are molecular weight, pitch and concentration by weight, is inherent to an optically active side chain and that the value is additive for compounds with two optically active side chains.