Incompressibility conditions in liquid crystals

Pleiner, Harald; Brand, Helmut R.

doi:10.1007/s00161-002-0098-9

Cited by 9 publications

(15 citation statements)

References 28 publications

(56 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The quantities ν 1 , ν 2 , ν 3 , γ 1 , and λ can be expressed through more commonly used Leslie viscosity coefficients [50,51]. Note that equating η ≡ ν 1 = ν 2 = ν 3 recovers the viscous stress tensor 2ηS of the isotropic incompressible fluid (last term in Eq.…”

Section: H Nematic Liquid Crystalmentioning

confidence: 99%

Waves at surfactant-laden liquid-liquid crystal interface

Lishchuk

2007

Phys. Rev. E

View full text Add to dashboard Cite

A theoretical study is presented of surface waves at a monomolecular surfactant film between an isotropic liquid and a nematic liquid crystal for the case when the surfactant film is in the isotropic two-dimensional fluid phase and induces homeotropic (normal to the interface) orientation of the nematic director. The dispersion relation for the surface waves is obtained, and different surface modes are analyzed with account being taken of the anchoring induced by the surfactant layer, the curvature energy of the interface, and the anisotropy of the viscoelastic coefficients. The dispersion laws for capillary and dilatational surface modes retain structure similar to that in isotropic systems, but involve anisotropic viscosity coefficients. Additional modes are related to relaxation of the nematic director field due to anchoring at the interface. The results can be used to determine different properties of nematic-surfactant-isotropic interfaces from experimental data on surface light scattering.

show abstract

Section: H Nematic Liquid Crystalmentioning

confidence: 99%

Waves at surfactant-laden liquid-liquid crystal interface

Lishchuk

2007

Phys. Rev. E

View full text Add to dashboard Cite

show abstract

“…is the strain-rate tensor, for the biaxial nematics is well known, we shall simply quote the result from literature [31,32]:…”

Section: Dissipative Termsmentioning

confidence: 99%

Poisson-bracket approach to the dynamics of bent-core molecules

Kung

2007

Phys. Rev. E

View full text Add to dashboard Cite

We generalize our previous work on the phase stability and hydrodynamic of polar liquid crystals possessing local uniaxial C∞v-symmetry to biaxial systems exhibiting local C2v-symmetry. Our work is motivated by the recently discovered examples of thermotropic biaxial nematic liquid crystals comprising bent-core mesogens, whose molecular structure is characterized by a non-polar body axis (n) as well as a polar axis (p) along the bisector of the bent mesogenic core which is coincident with a large, transverse dipole moment. The free energy for this system differs from that of biaxial nematic liquid crystals in that it contains terms violating the p → −p symmetry. We show that, in spite of a general splay instability associated with these parity-odd terms, a uniform polarized biaxial state can be stable in a range of parameters. We then derive the hydrodynamic equations of the system, via the Poisson-bracket formalism, in the polarized state and comment on the structure of the corresponding linear hydrodynamic modes. In our Poisson-bracket derivation, we also compute the flow-alignment parameters along the three symmetry axes in terms of microscopic parameters associated with the molecular geometry of the constituent biaxial mesogens.

show abstract

“…, and where the five viscous coefficients ν i satisfy the usual inequalities for a uniaxial system [40].…”

Section: F Irreversible Dynamics and Entropy Productionmentioning

confidence: 99%

Macroscopic dynamics of polar nematic liquid crystals

2006

Self Cite

View full text Add to dashboard Cite

We present the macroscopic equations for polar nematic liquid crystals. We consider the case where one has both, the usual nematic director, n[over ] , characterizing quadrupolar order as well as the macroscopic polarization, P , representing polar order, but where their directions coincide and are rigidly coupled. In this case one has to choose P as the independent macroscopic variable. Such equations are expected to be relevant in connection with nematic phases with unusual properties found recently in compounds composed of banana-shaped molecules. Among the effects predicted, which are absent in conventional nematic liquid crystals showing only quadrupolar order, are pyro-electricity and its analogs for density and for concentration in mixtures as well as a flow alignment behavior, which is more complex than in usual low molecular weight nematics. We also discuss the formation of defect structures expected in such systems.

show abstract

Incompressibility conditions in liquid crystals

Cited by 9 publications

References 28 publications

Waves at surfactant-laden liquid-liquid crystal interface

Waves at surfactant-laden liquid-liquid crystal interface

Poisson-bracket approach to the dynamics of bent-core molecules

Macroscopic dynamics of polar nematic liquid crystals

Contact Info

Product

Resources

About