Photoresponsive glass-forming butadiene-based chiral liquid crystals with circularly polarized photoluminescence

The synthesis and study of the photo and thermoresponsive behavior of a series of novel trimesogenes consisting of a diphenylbutadiene core linked to cholesterol moietes on either side via flexible alkyl chains are reported. These molecules possess the combined glass forming properties of bischolesterols and photochromic and luminescent properties of the butadiene moity. The pitch of the cholesteric phase of these materials could be continuosly varied thermally and photochemically, making it possible to tune the color of the film over the entire visible region. The color images thus generated could be stabilized by coverting them to N glasses. These materials were also highly photoluminescent, exhibiting circularly polarized characteriztics in the glassy liquid-crystalline state even by linearly polarized excitation.