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Subject flexoelectric

In addition to the pear-shaped molecules, bent-shaped molecules were used to illustrate the dipolar origin of the flexoelectric effects in nematic liquid crystals. It was assumed that the constituent molecules of the nematic liquid crystals are free to rotate around their axes, and in the absence of electric fields, their dipole moments average out so the net polarization of the material is zero. However, when liquid crystals made from polar pear- or banana-shaped molecules are subjected to splay or bend deformations, respectively, they can become macroscopically polar, because the polar structures correspond to a more efficient packing of the molecules. It follows from symmetry considerations that the deformation-induced fiexo-electric polarization Pa can be written as ... [Pg.68]

Converse flexoelectric studies of lyotropic liquid crystals, such as vesicles, is still an active subject. Notably, the sensory mechanism of outer hair cell composite membranes " can be understood by the flexoelectric properties of the lipid bilayer. The converse of this effect, i.e., a voltage-generated curvature, has also been observed and was discussed by Todorov et Another related phenomenon is the ferroelectricity which results from the tilted layered structures of chiral molecules, which has been discussed extensively since the 1980s.Ferroelectric phases are called... [Pg.69]

Naturally, this volume could include only a limited number of topics, which have been selected according to the interests and fields of expertise of the contributors thus we cannot claim that all aspects of flexoelectricity are fully addressed. Nevertheless, we think that the chapters provide a state-of-the-art comprehensive picture of the subject. Readers interested in more details will easily find in the references other works where related topics are discussed. [Pg.297]

FIGURE 4.29. The flexoelectric effect, (a) The structure of an undeformed nematic hquid crystal with pear- and banana-shaped molecules (b) the same nematic hquid crystal subjected to splay and bend deformations, respectively (c) the experimental configuration atnd (d) the distribution of the director along the z-axis due to the flexoelectric effect. [Pg.191]


See other pages where Subject flexoelectric is mentioned: [Pg.347]    [Pg.34]    [Pg.39]    [Pg.69]    [Pg.71]    [Pg.186]    [Pg.327]   
See also in sourсe #XX -- [ Pg.43 , Pg.113 , Pg.114 , Pg.146 , Pg.147 , Pg.167 , Pg.169 , Pg.171 , Pg.173 ]




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Flexoelectric

Flexoelectricity

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