Intercalated smectic a phases in banana-shaped liquid crystals with carbonate end groups.
Novel, symmetrical, bent-core mesogens, namely substituted 1,3-phenylenebis{4'-[(ethoxycarbonyl)oxy]-1,1'-biphenyl}-4-carboxylates, are prepared with carbonate groups at both ends of the molecules. The mesophase properties are investigated for different electron-donating and -withdrawing substituents connected to the central ring at different positions. These compounds exhibit nematic and/or smectic A intercalated (SmA(int)) mesophases. Electro-optical studies show a very significant electric-field-induced biaxiality that is fast (<1 ms) and large (0.03) associated with a high birefringence (0.33 at 500 nm, 10 V mum(-1) field) for the unsubstituted analogue. For one substance this effect is observable from above 100 degrees C down to room temperature. Such electric-field-induced biaxiality may find practical applications in fast electro-optic modulation devices.
Fodor-Csorba
Katalin
K
Research Institute for Solid State Physics and Optics Hungarian Academy of Sciences, P.O. Box 49, 1525 Budapest, Hungary. fodor@szfki.hu
Jákli
Antal
A
Vajda
Anikó
A
Prasad
S Krishna
SK
Shankar Rao
Doddamane S
DS
Dong
Ronald Y
RY
Xu
Jiadi
J
Galli
Giancarlo
G