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Related papers: Mesoscale Structure of Chiral Nematic Shells

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A two-dimensional or quasi-two-dimensional nematic liquid crystal refers to a surface confined system. When such a system is further confined by external line boundaries or excluded from internal line boundaries, the nematic directors form…

Soft Condensed Matter · Physics 2022-04-27 Xiaomei Yao , Lei Zhang , Jeff Z. Y. Chen

Using computer simulations we investigate the microscopic structure of the singular director field within a nematic droplet. As a theoretical model for nematic liquid crystals we take hard spherocylinders. To induce an overall topological…

Soft Condensed Matter · Physics 2009-10-31 J. Dzubiella , M. Schmidt , H. Loewen

The properties of liquid crystals can be modelled using an order parameter which describes the variability of the local orientation of rod-like molecules. Defects in the director field can arise due to external factors such as applied…

Numerical Analysis · Mathematics 2019-10-08 Craig S. MacDonald , John A. Mackenzie , Alison Ramage

Optical birefringence measurements on a rod-like liquid crystal (8OCB), imbibed in silica channels (7 nm diameter), are presented and compared to the thermotropic bulk behavior. The orientational and positional order of the confined liquid…

Soft Condensed Matter · Physics 2015-05-20 Andriy V. Kityk , Patrick Huber

Handedness of the director twist in cholesteric liquid crystals is commonly assumed to be the same throughout the medium, determined solely by the chirality of constituent molecules or chiral additives, albeit distortions of the…

Soft Condensed Matter · Physics 2017-04-26 P. J. Ackerman , I. I. Smalyukh

We demonstrate that a first order isotropic-to-nematic phase transition in liquid crystals can be succesfully modeled within the generalized Landau-de Gennes theory by selecting an appropriate combination of elastic constants. The numerical…

Soft Condensed Matter · Physics 2019-02-19 Dmitry Golovaty , Young-Ki Kim , Oleg D. Lavrentovich , Michael Novack , Peter Sternberg

We study the effects of chirality at the segment scale on the thermodynamics of block copolymer melts using self consistent field theory. In linear diblock melts where segments of one block prefer a twisted, or cholesteric, texture, we show…

Soft Condensed Matter · Physics 2015-06-11 Wei Zhao , Thomas P. Russell , Gregory M. Grason

A computational study of morphological instabilities of a two-dimensional nematic front under directional growth was performed using a Landau-de Gennes type quadrupolar tensor order parameter model for the first-order isotropic/nematic…

Soft Condensed Matter · Physics 2009-08-20 Ezequiel R. Soulé , Nasser Mohieddin Abukhdeir. Alejandro D. Rey

We propose a continuum tensorial model for chiral smectic C (SmC$^*$) liquid crystals using a tensor-valued order parameter $\mathbf{Q}$ to describe orientational order and a real-valued order parameter $\delta\rho$ to capture layer…

Soft Condensed Matter · Physics 2025-09-09 Jingmin Xia , Jinbing Wu , Yucen Han

Chiral nematic or cholesteric liquid crystals (LCs) are mesophases with long-ranged orientational order featuring a quasi-layered periodicity imparted by a helical configuration but lacking positional order. Doping molecular cholesteric LCs…

Present work is a theoretical study on the stability of the thermotropic biaxial nematic liquid crystal phase in model systems. Its main aim is to present the phase diagrams of spatially uniform liquid mesophases and to identify the…

Soft Condensed Matter · Physics 2009-07-07 Piotr Grzybowski

A nematic liquid-crystal gel is a macroscopically homogeneous elastic medium with the rotational symmetry of a nematic liquid crystal. In this paper, we develop a general approach to the study of these gels that incorporates all underlying…

Soft Condensed Matter · Physics 2009-11-07 T. C. Lubensky , Ranjan Mukhopadhyay , Leo Radzihovsky , Xiangjun Xing

We develop a theory of point defects in cholesterics and textures in spherical droplets with normal anchoring. The local structure of chiral defects is described by singularity theory and a smectic-like gradient field establishing a nexus…

Soft Condensed Matter · Physics 2019-04-11 Joseph Pollard , Gregor Posnjak , Gareth P. Alexander , Simon Copar , Igor Musevic

The possible symmetries of the biaxial nematic phase are examined against the implications of the presently available experimental results. Contrary to the widespread notion that biaxial nematics have orthorhombic symmetry, our study shows…

Soft Condensed Matter · Physics 2010-04-15 Panagiota K. Karahaliou , Alexandros G. Vanakaras , Demetri J. Photinos

Liquid crystalline systems exhibiting both macroscopic chirality and smectic order experience frustration resulting in mesophases possessing complex three-dimensional order. In the twist-grain-boundary phase, defect lattices mediate the…

Soft Condensed Matter · Physics 2009-12-18 Elisabetta A. Matsumoto , Gareth P. Alexander , Randall D. Kamien

Frustration is a powerful mechanism in condensed matter systems, driving both order and co plexity. In smectics, the frustration between macroscopic chirality and equally spaced layers generates textures characterised by a proliferation of…

Soft Condensed Matter · Physics 2016-11-14 Elisabetta A. Matsumoto , Randall D. Kamien , Gareth P. Alexander

A robust route for the biased production of single-handed chiral structures has been found in generating non-spherical, multi-component double emulsions using microfluidics. The specific type of handedness is determined by the final packing…

Soft Condensed Matter · Physics 2018-04-20 Laura L. A. Adams , Samuel A. Ocko

This review introduces the elasticity theory of two-dimensional crystals and nematic liquid crystals on curved surfaces, the energetics of topological defects (disclinations, dislocations and pleats) in these ordered phases, and the…

Soft Condensed Matter · Physics 2014-01-21 Vinzenz Koning , Vincenzo Vitelli

Molecular chirality leads to a wonderful variety of equilibrium structures, from the simple cholesteric phase to the twist-grain-boundary phases, and it is responsible for interesting and technologically important materials like…

Soft Condensed Matter · Physics 2007-05-23 T. C. Lubensky , A. B. Harris , Randall D. Kamien , Gu Yan

We study stability and distortions of liquid crystal nematic order in a cell with a random heterogeneous substrate. Modeling this system as a bulk xy model with quenched disorder confined to a surface, we find that nematic order is…

Soft Condensed Matter · Physics 2010-05-05 Quan Zhang , Leo Radzihovsky