Landau Theory of Wall-Induced Phase Nucleation and Pretransitional Birefringence at the Isotropic-Nematic Transition
نویسندگان
چکیده
منابع مشابه
Critical behavior at the isotropic-to-nematic phase transition in a bent-core liquid crystal.
Magnetic birefringence and dynamic light scattering measurements of orientational order parameter fluctuations at the isotropic-nematic phase transition of a bent-core liquid crystal reveal a pretransitional temperature dependence consistent with the standard Landau-deGennes mean field theory. However, as follows: the transition in the bent-core compound is more weakly first order (TNI-T* appro...
متن کاملInvestigation into the temperature dependence of isotropic- nematic phase transition of Gay- Berne liquid crystals
Density functional approach was used to study the isotropic- nematic (I-N) transition and calculate the values of freezing parameters of the Gay- Berne liquid crystal model. New direct and pair correlation functions of a molecular fluid with Gay- Berne pair potential were used. These new functions were used in density functional theory as input to calculate the isotropic- nematic transition den...
متن کاملPretransitional Nematic Ordering in Liquid Crystals with Dispersed Polymer Networks
The birefringence induced by partially ordered polymer networks dispersed in an isotropic phase of liquid crystals is studied. Polymer networks were formed by the polymerization of 1–4 % mixtures of prepolymer in the nematic phase of liquid crystals. The partial nematic ͑paranematic͒ ordering is analyzed in terms of the Landau–de Gennes approach using a simple model of an array of thin fibrils, w...
متن کاملAggregation, Pretransitional Behavior, And Optical Properties In The Isotropic Phase Of Lyotropic Chromonic Liquid Crystals Studied In High Magnetic Fields
Aggregation, pretransitional behavior, and optical properties in the isotropic phase of lyotropic chromonic liquid crystals studied in high magnetic fields a We report results on the high-field magneto-optical response of four aqueous, lyotropic, chromonic liquid crystal formulations in the isotropic phase. Measurements of the field-induced birefringence at temperatures above the isotropic-nema...
متن کاملSingular Pretransitional Behavior of the Electric Field-Dependent Part of the Thermodynamic Quantities of Strongly Polar Mesogenic Liquids in the Isotropic Phase
A new interpretation of the pretransitional temperature behavior of the static dielectric permittivity and its derivative in terms of the basic thermodynamic quantities: the internal energy, the entropy, and the Helmholtz free energy is presented. It was shown that in the case of strongly polar mesogenic compounds (as the homologous series of alkylcyanobiphenyls) the electric field-induced incr...
متن کامل