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.

DYNAMIC LIGHT SCATTERING IN LC-440 NEMATIC LIQUID CRYSTAL

2014 ◽  
Vol 73 (11) ◽  
pp. 977-983
Author(s):  
A. P. Fedoryako ◽  
A. I. Kocherzhin ◽  
M. P. Kukhtin ◽  
E. I. Chernyakov
Keyword(s):  
Liquid Crystal ◽  
Light Scattering ◽  
Dynamic Light Scattering ◽  
Nematic Liquid Crystal

Effect of Different Layer Thicknesses and Boundary Conditions of Confined Liquid Crystal on Dynamics of Director Relaxation: Dynamic Light Scattering Investigations

2003 ◽  
Vol 790 ◽  
Author(s):  
Sarmistha Basu ◽  
Fouad M. Aliev
Keyword(s):  
Liquid Crystal ◽  
Light Scattering ◽  
Dynamic Light Scattering ◽  
Boundary Conditions ◽  
Nematic Phase ◽  
Pore Wall ◽  
Surface Relaxation ◽  
Relaxation Processes ◽  
Slow Process ◽  
Relaxation Dynamic

ABSTRACTDynamic light scattering (DLS) has been used to study the influence of boundary conditions (planar-axial and homeotropic-radial) and layer thickness of liquid crystal (8CB) confined to cylindrical pores on phase transitions and relaxation of director orientational fluctuations. For confined 8CB in the nematic phase two well-defined relaxation processes were observed for both axial and radial orientations of the liquid crystal. The first relaxation is qualitatively associated with bulk-like nematic director fluctuations. The second relaxation (with relaxation time slower than the first one) is most likely due to the fluctuations in the layers nearest the wall surface. In samples with radial boundary conditions, we observed the onset of smectic-A phase order formation on the pore wall even though the rest of the liquid crystal could be in the nematic phase. The influence of pore wall-liquid crystal interactions on the properties of the confined 8CB was stronger for radial boundary conditions of confined liquid crystal, than in the case of axial orientation‥ The separation between the first and the second (slow) process was clearer for thinner layers and the amplitude of the slow process was greater for thinner layers. This suggests that the slow process was related to surface relaxation of director fluctuations.

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