PHASE-BEHAVIOR AND MEMORY EFFECT OF AN INDUCED SMECTIC LC BLEND CONTAINING A PHOTOCHROMIC DYE

The binary mixture of two low-molecular-weight liquid crystals (8CB/PA OE) forms an induced smectic phase over a wide range of mixing weight proportion and temperature. The photosensitive material was prepared u sing the liquid crystal mixture doped with a photochromic dye, 4-pheny lazoaniline (PAA). The change of the configuration of dopant dye pertu rbed the liquid crystalline order, and a reversible turbid-transparent change was observed upon photo-irradiation as well as upon applicatio n of an electric field. In addition, the effects of an applied field o n the mesogenic group and molecular dipole alignments were studied by dielectric relaxation spectroscopy. (C) 1998 Elsevier Science B.V.