# Viscoelasticity of ambient-temperature nematic binary mixtures of bent-core and rodlike molecules.

@article{Sathyanarayana2012ViscoelasticityOA,
title={Viscoelasticity of ambient-temperature nematic binary mixtures of bent-core and rodlike molecules.},
author={P. M. Sathyanarayana and Venkata Subba Rao Jampani and M {\vS}karabot and Igor Musevic and Khoa V. Le and Hideo Takezoe and Surajit Dhara},
journal={Physical review. E, Statistical, nonlinear, and soft matter physics},
year={2012},
volume={85 1 Pt 1},
pages={
011702
}
}
• P. Sathyanarayana, +4 authors S. Dhara
• Published 2012
• Materials Science, Medicine
• Physical review. E, Statistical, nonlinear, and soft matter physics
We report measurements of the temperature variations of physical parameters in ambient-temperature nematic liquid crystal mixtures of bent-core (BC) and rodlike molecules (5CB): birefringence Δn; static dielectric constants ε(||) and ε(⊥); splay K(11) and bend K(33) elastic constants; rotational viscosity γ(1); and diffusion coefficients D(||) and D(⊥) of a microsphere. Both Δn and ε(||) decreases rapidly with increasing BC concentration, whereas ε(⊥) remains almost constant. At a shifted… Expand
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#### References

SHOWING 1-10 OF 91 REFERENCES
Splay-bend elasticity and rotational viscosity of liquid crystal mixtures of rod-like and bent-core molecules
• Chemistry
• 2011
We report temperature dependent measurements of birefringence (Δn), splay (K11), bend (K33) elastic constants and rotational viscosity (γ1) of mixtures of rod-like and bent-core molecules. K11 and ΔnExpand
Anomalous temperature dependence of elastic constants in the nematic phase of binary mixtures made of rodlike and bent-core molecules.
• Materials Science, Medicine
• Physical review letters
• 2007
We report on two anomalous trends in the temperature dependences of the splay (K11) and bend (K33) elastic constants in the nematic (N) phase of mixtures of compounds with rodlike (R) and bent-coreExpand
Elastic constants and orientational viscosities of a bent-core nematic liquid crystal.
• Materials Science, Medicine
• Physical review. E, Statistical, nonlinear, and soft matter physics
• 2011
Using a combination of dynamic light scattering and Freedericksz transitions induced in applied magnetic and electric fields, we have determined the absolute magnitudes of the Frank elastic constantsExpand
Permittivity, conductivity, elasticity, and viscosity measurements in the nematic phase of a bent-core liquid crystal.
• Chemistry, Medicine
• The journal of physical chemistry. B
• 2010
Measurements of dielectric permittivity epsilon, electrical conductivity sigma, elastic moduli k(ii), and rotational viscosity gamma for a bent-core nematic liquid crystal show that viscous relaxation is more complex than in calamitic systems involving at least a two-step process. Expand
Rotational Viscosity of a Bent-Core Nematic Liquid Crystal
We report the detailed measurements of the rotational viscosity (γ1) of a bent-core nematic liquid crystal exhibiting positive dielectric anisotropy by measuring the decay time of the optical phaseExpand
Orientational order in liquid crystals exhibited by some binary mixtures of rod-like and bent-core molecules
• Materials Science, Medicine
• The European physical journal. E, Soft matter
• 2010
We report measurements of the temperature variations of the optical birefringence in the nematic (N) and partial bilayer SmA (SmAd) phases in 4-n-octyloxy 4′ -cyanobiphenyl made of rod-like (R)Expand
Viscosities of a bent‐core nematic liquid crystal
• Materials Science
• 2008
Viscosity measurements are reported for a bent‐core nematic liquid crystal, 4‐ chloro‐1,3‐phenylenebis{4‐[4′‐(9‐decenyloxy)benzoyloxy]} benzoate (ClPbis10BB). The rotational viscosity was measured byExpand
Splay bend elasticity of a bent-core nematic liquid crystal.
• P. Sathyanarayana, +5 authors S. Dhara
• Materials Science, Medicine
• Physical review. E, Statistical, nonlinear, and soft matter physics
• 2010
The splay (K11) and bend (K33) elastic constants in the nematic phase of a bent-core liquid crystal are measured and the small K33 is explained on the basis of strong coupling of the bent shape of the molecules with the bend distortion. Expand
Kerr constant and third-order nonlinear optic susceptibility measurements in a liquid crystal composed of bent-shaped molecules.
• S. Dhara, +6 authors H. Takezoe
• Physics, Medicine
• Physical review. E, Statistical, nonlinear, and soft matter physics
• 2008
The temperature-dependent Kerr constant is found to be in good agreement with the predictions of the Landau-de Gennes theory and the experimental results are compared with those in a calamitic liquid crystal material with negative dielectric anisotropy in the nematic phase. Expand
Alignment of unconventional nematic liquid crystals
• Materials Science
• 2011
Planar (homogeneous) and homeotropic alignment of some unconventional nematic liquid crystals with both positive (Δε > 0) and negative (Δε < 0) dielectric anisotropies are studied on planar (AL-1254)Expand