Induced Circular Dichroism in Liquid Crystalline Phases

7 Induced Circular Dichroism in Liquid Crystalline Phases 

In Section 3.4.6 it was noted that chiral mesophases behave as chiral perturbation moieties for achiral molecules inserted to the mesophases. Here, only relations between the observed signs in LCICD and the pitch-dependent CD in liquid crystalline systems, and the helical sense of the liquid crystalline phases are described. 

Several unique optical properties arise from helical structures of cholesteric liquid crystals. 

1) For light incident parallel to the helix axis in a cholesteric phase, only the lowest-order reflection is allowed. 

2) Only the component of optical polarization for which an instantaneous electric field matches the helical cholesteric directors is strongly reflected. 

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