A novel series of styrene‐based liquid crystal monomers displaying either nematic or chiral nematic phases

2006 ◽  
Vol 33 (9) ◽  
pp. 1021-1026
Author(s):  
Neil B. McKeown ◽  
Anthony Cook
2019 ◽  
Author(s):  
Adam Al-Janabi ◽  
Richard Mandle

<p>The nematic twist-bend (N<sub>TB</sub>) liquid crystal phase possesses a local helical structure with a pitch length of a few nanometres and is the first example of spontaneous symmetry breaking in a fluid system. All known examples of the N­<sub>TB­</sub> phase occur in materials whose constituent mesogenic units are aromatic hydrocarbons. It is not clear if this is due to synthetic convenience or a <i>bona fide</i> structural requirement for a material to exhibit this phase of matter. In this work we demonstrate that materials consisting largely of saturated hydrocarbons could also give rise to this mesophase. Furthermore, replacement of 1,4-disubstituted benzene with <i>trans</i> 1,4-cyclohexane or even 1,4-cubane does not especially alter the transition temperatures of the resulting material nor does it appear to impact upon the heliconical tilt angle, suggesting the local structure of the phase is unperturbed. Calculating the probability distribution of bend angles reveals that the choice of isosteric group has little impact on the overall molecular shape, demonstrating the shape-driven nature of the N<sub>TB</sub> phase. </p>


Tetrahedron ◽  
2020 ◽  
pp. 131870
Author(s):  
Yuki Arakawa ◽  
Kenta Komatsu ◽  
Yuko Ishida ◽  
Kazunobu Igawa ◽  
Hideto Tsuji

2021 ◽  
Author(s):  
Huanan Yu ◽  
Wentao Qu ◽  
Feng Liu ◽  
Georg H. Mehl

Gold nanoparticles (NPs) were surface functionalized with hexanethiol groups and chiral nematic discogen ligands. A superlattice, liquid crystal behaviour and helix formation of the discs and a second helical organisation of the NPs were detected.


2021 ◽  
Vol 119 ◽  
pp. 111306
Author(s):  
Hossein mehrzad ◽  
Ezeddin Mohajerani ◽  
Mohammad Mohammadimasoudi ◽  
Kristiaan Neyts

2011 ◽  
Vol 181-182 ◽  
pp. 257-260
Author(s):  
David Statman ◽  
Andrew Jockers ◽  
Daniel Brennan

Chiral nematic liquid crystals prepared with Grandjean texture demonstrate a photonic bandgap whose central wavelength is proportional to the pitch length, P, of the liquid crystal and whose width is given by (ne – no)P. We show that methyl red doped chiral nematics undergo a shift in the photonic bandgap upon photo-isomerization. This shift is a result of (1) photo-induced change in anchoring energy on the nematic surface, and (2) change in the natural pitch length from the photo-isomerization of the azo dye.


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