Effect of Dopant Structure on Birefringences and Symmetric Tensor Invariants of Lyotropic Nematic Phases

Year 2018, Volume: 14 Issue: 2, 229 - 235, 30.06.2018

Erol Akpınar

https://doi.org/10.18466/cbayarfbe.403800

Abstract

In this study,
we investigated the effect of the dopant structure on the birefringences and
the symmetric tensor invariants of lyotropic discotic nematic (N_D),
calamitic nematic (N_C) and biaxial nematic (N_B) phases.
Lyotropic host mixture consisted of potassium laurate (KL)/decanol
(DeOH)/water. Some dopant molecules were added to this host mixture to obtain
quaternary mixtures and to investigate the nematic phase properties by
polarizing optical microscopy and laser conoscopy. It was found that the dopant
molecules with aromatic ring affect the birefringences and symmetric tensor
invariants more efficiently than those with straight alkyl chain. 

Keywords

Lyotropic liquid crystals, nematic phases, birefringences, symmetric tensor invariants, laser conoscopy, polarizing optical microscopy

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