scholarly journals Effect of the degree of protonation of amino acid dopants in Chirality amplification in DSCG Lyotropic Nematic phases.

2021 ◽  
Author(s):  
Fernán Berride ◽  
Eduardo Troche-Pesqueira ◽  
Richard G. Weiss ◽  
Armando Navarro-Vázquez ◽  
María Magdalena Cid
Keyword(s):  
Liquid Crystal ◽  
Amino Acid ◽  
Nematic Phase ◽  
Lyotropic Liquid Crystal ◽  
Disodium Cromoglycate ◽  
Chiral Molecules ◽  
Cholesteric Phase ◽  
Nematic Phases ◽  
Helical Twisting Power ◽  
Acid Dopants

Disodium Cromoglycate (DSCG), a lyotropic liquid crystal in water, is shown to be an amplifier of chirality when doped with small chiral molecules. Here, we study the behaviour of the DSCG nematic phase in the presence of three aminoacids with different degrees of protonation: L-Alanine, L-Arginine·HCl and L-Arginine. The results demonstrate that the sign of the helicity of the doped nematic phase (i.e., a cholesteric phase) depends on the sign of the Helical Twisting Power of the dopant.

A new soap/detergent/water lyotropic liquid crystal with a biaxial nematic phase

1989 ◽  
Vol 5 (6) ◽  
pp. 1669-1675 ◽  
Author(s):  
E. A. Oliveira ◽  
L. Liebert ◽  
A. M. Figueiredo Neto
Keyword(s):  
Liquid Crystal ◽  
Nematic Phase ◽  
Lyotropic Liquid Crystal ◽  
Biaxial Nematic ◽  
Biaxial Nematic Phase

Elasticity, viscosity, and orientational fluctuations of a lyotropic chromonic nematic liquid crystal disodium cromoglycate

Soft Matter ◽  
2014 ◽  
Vol 10 (34) ◽  
pp. 6571-6581 ◽  
Author(s):  
Shuang Zhou ◽  
Krishna Neupane ◽  
Yuriy A. Nastishin ◽  
Alan R. Baldwin ◽  
Sergij V. Shiyanovskii ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Light Scattering ◽  
Dynamic Light Scattering ◽  
Nematic Liquid Crystal ◽  
Nematic Phase ◽  
Elastic Moduli ◽  
Disodium Cromoglycate ◽  
Viscosity Coefficients ◽  
Self Assembled

Using dynamic light scattering, we study orientational fluctuation modes in the nematic phase of a self-assembled lyotropic chromonic liquid crystal disodium cromoglycate and measure the Frank elastic moduli and viscosity coefficients.

Computer Simulation of Chiral Liquid Crystal Phases IX. Chiral Induction in Guest-host Systems - Calculation of the Helical Twisting Power

1999 ◽  
Vol 54 (12) ◽  
pp. 747-754 ◽  
Author(s):  
Reiner Memmer ◽  
Folkert Janssen
Keyword(s):  
Liquid Crystalline ◽  
Dopant Concentration ◽  
System Size ◽  
Chiral Molecules ◽  
Cholesteric Phase ◽  
Chiral Induction ◽  
Chiral Liquid Crystal ◽  
Liquid Crystalline Phases ◽  
Helical Twisting Power

Abstract The chiral induction in liquid crystalline phases was studied by Monte Carlo simulation of the chiral Lebwohl-Lasher model. Binary guest-host systems composed of achiral and chiral molecules as well as of different chiral molecules were investigated in dependence on the composition. A cholesteric phase was induced by dissolving a small fraction of chiral molecules in a nematic phase. For dilute solutions the equilibrium pitch was found to be a linear function of the chiral dopant concentration. Independent of system size effects the application of self-determined boundary conditions enabled the determination of the symmetry adapted quantities for the chiral induction, the helical twisting power (HTP) and the achiral helical twisting power (AHTP). Additionally, a different orientational behaviour of enantiomeric dopants in the chiral surroundings of a cholesteric host phase has been determined.

On the Unified Theory for Non-Equilibrium Phenomena in the Isotropic and Nematic Phases of a Liquid Crystal; Spatially Inhomogeneous Alignment

1981 ◽  
Vol 36 (6) ◽  
pp. 554-558 ◽  
Author(s):  
S. Hess ◽  
I. Pardowitz
Keyword(s):  
Liquid Crystal ◽  
Order Parameter ◽  
Nematic Phase ◽  
Unified Theory ◽  
Spatially Inhomogeneous ◽  
Previously Treated ◽  
Spatial Derivatives ◽  
Nematic Phases ◽  
Flow Alignment ◽  
Derivatives Of

Abstract A nonlinear equation is derived which describes the relaxation of the alignment and the flow alignment in the isotropic and nematic phases of a liquid crystal. In addition to the previously treated case, contributions associated with spatial derivatives of the alignment are taken into account which stem from gradient terms occuring in the free energy (elastic energy) and from the flux of the alignment. Some applications are discussed. In particular, the Leslie and Frank coefficients of the nematic phase are expressed in terms of the equilibrium alignment order parameter and coefficients which are meaningful in both phases

scholarly journals On the Miscibility of Nematic Liquid Crystals with Ionic Liquids and Joint Reaction for High Helical Twisting Power Product(s)

Materials ◽  
2021 ◽  
Vol 15 (1) ◽  
pp. 157
Author(s):  
Maciej Czajkowski ◽  
Joanna Feder-Kubis ◽  
Bartłomiej Potaniec ◽  
Łukasz Duda ◽  
Joanna Cybińska
Keyword(s):  
Ionic Liquids ◽  
Liquid Crystal ◽  
Liquid Crystals ◽  
Nematic Phase ◽  
Nematic Liquid Crystals ◽  
Organic Salt ◽  
Power Product ◽  
Twisted Nematic ◽  
Helical Twisting Power ◽  
Phase Phase

Mixtures of nematic liquid crystals (LCs) with chiral ionic liquids (CILs) may find application as active materials for electrically driven broadband mirrors. Five nematic liquid crystal hosts were mixed with twenty three ionic liquids, including chiral ones, and studied in terms of their miscibility within the nematic phase. Phase diagrams of the mixtures with CILs which exhibited twisted nematic phase were determined. Miscibility, at levels between 2 and 5 wt%, was found in six mixtures with cyanobiphenyl-based liquid crystal host—E7. On the other hand, the highest changes in the isotropization temperature was found in the mixtures with isothiocyanate-based liquid crystal host—1825. Occurrence of chemical reactions was found. A novel chiral binaphtyl-based organic salt [N11116][BNDP] was synthesized and, in reaction to the 1825 host, resulted in high helical twisting power product(s). Selectivity of the reaction with the isothiocyanate-based liquid crystal was found.

X-ray studies of the surface and bulk structure of the isotropic and nematic phase of a lyotropic liquid crystal

1991 ◽  
Vol 43 (12) ◽  
pp. 6815-6825 ◽  
Author(s):  
G. Swislow ◽  
D. Schwartz ◽  
B. M. Ocko ◽  
P. S. Pershan ◽  
J. D. Litster
Keyword(s):  
Liquid Crystal ◽  
Nematic Phase ◽  
Lyotropic Liquid Crystal ◽  
X Ray ◽  
Bulk Structure
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