Abstract
The dielectric and current voltage properties of 4-cyano-4’-n-heptylbiphenyl doped LC1 and LC2 salicylaldimine compounds
have been investigated. The polarizing microscopy and differential scanning calorimetry results show that the
salicylaldimine compounds (LC1, LC2) exhibit liquid crystalline properties. The salicylaldimine compound LC1 exhibits SmC
and SmA mesophases, while LC2 exhibits only SmA mesophase. The dielectric anisotropy of the LCs was found to vary
from positive type to negative type. The LC1 liquid crystal significantly the dielectrical anisotropy behavior of the 7CB. The
dielectrical relaxation mechanism analyzed by the Cole-Cole plots of the liquid crystals is close to Debye type relaxation
behavior. The current voltage characteristics indicate that the 7CB and 7CB/LC1 liquid crystals exhibit voltage-controlled
differential negative resistance (VCNR) behavior. It is evaluated that the molecular orientation and electrical properties of
the 7CB liquid crystal can be controlled by salicylaldimine compounds.
Keywords
Liquid crystal, Dielectric anisotropy, Salicylaldimine.
Citation
N. YILMAZ CANLI, F. YAKUPHANOĞLU, B. BILGIN-ERAN, Molecular orientation and electrical properties of 4-cyano-4’-n-heptylbiphenyl-salicylaldimine compound composite liquid crystals by dielectric impedance spectroscopy and current-voltage techniques, Optoelectronics and Advanced Materials - Rapid Communications, 3, 7, July 2009, pp.731-736 (2009).
Submitted at: June 19, 2009
Accepted at: July 20, 2009