Questions tagged [liquid-crystal]

Liquid crystals (LCs) are matter in a state that has properties between those of conventional liquid and those of solid crystal.

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What is Landau-deGenes Expansion?

I am an undergraduate student in an introduction to condensed matter physics course and I am struggling to understand the process of Landau expansion of order parameter S as it relates to liquid ...
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Difference between various theories of liquid crystals

Can somebody explain as to what is the difference between various theories of liquid crystals? 1) Maier-Saupe Theory 2) Onsager Theory 3) Landau theory What's the advantages and disadvantages or ...
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Liquid crystals resource recommendation

I'm going to work with liquid crystals during my summer internship and I am so woefully unprepared. Could you please recommend me some book or some review articles that cover the essential concepts ...
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How can I deduce the magnetic susceptibility tensor of a biaxial liquid crystal in its nematic phase?

I know from de Gennes' book [1] that the (magnetic) susceptibility tensor $\chi_{\alpha\beta}$ of an uniaxial liquid crystal in its nematic phase can be written as \begin{align} \chi_{\alpha\beta}&...
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What it means to be that liquid crystals are thermodynamically stable?

When we heat some solids, they don't pass into liquid state directly. Rather they form a mesomorphic phase called liquid crystals.Now when we heat liquid crystal, they are converted into pure liquids. ...
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Why use class multiplication to describe topological entangling and merging?

I'm studying some references about topological defects in ordered media like Soft matter physics: An introduction by Kleman and the Review modern physics paper The topological theory of defects in ...
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What is the representation of the different classes of nontrivial textures in an ordered field of biaxial nematics in terms of $SU(2)$-like rotations?

I was reading Mermin's classic review on Topological Defects in Ordered Media, in which he describes ordered media with non-Abelian Fundamental Groups by taking the example of biaxial nematics with ...
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Are the curvature Frank elastic constants of the liquid crystal the no-zero elements of the 6x6 elastic (stiffness) matrix?

I was reading Landau's book on elasticity theory, and it raised this doubt. Can anyone help me?
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Molecular field meaning in Liquid Crystal Theory

Given the Frank-De Gennes free energy $F = \int f(\boldsymbol{p},\nabla\boldsymbol{p}, ...)\ d\boldsymbol{x},$ for liquid crystals (see De Gennes-Prost, p. 107, formula 3.21), the vector $$h_{i}=-\...