scholarly journals Reversibly tunable helicity induction and inversion in liquid crystal self-assembly by a planar chiroptic trigger molecule

2009 ◽  
pp. 3609 ◽  
Author(s):  
Manoj Mathews ◽  
Nobuyuki Tamaoki
Keyword(s):  
Liquid Crystal ◽  
Self Assembly ◽  
And Inversion ◽  
Trigger Molecule

Reversible microscale assembly of nanoparticles driven by the phase transition of a thermotropic liquid crystal

2017 ◽  
Author(s):  
Niamh Mac Fhionnlaoich ◽  
Stephen Schrettl ◽  
Nicholas B. Tito ◽  
Ye Yang ◽  
Malavika Nair ◽  
...  
Keyword(s):  
Phase Transition ◽  
Liquid Crystal ◽  
Self Assembly ◽  
Nematic Phase ◽  
Hierarchical Control ◽  
Building Blocks ◽  
Model System ◽  
Microscopic Level ◽  
Reversible Process ◽  
Thermotropic Liquid Crystal

The arrangement of nanoscale building blocks into patterns with microscale periodicity is challenging to achieve via self-assembly processes. Here, we report on the phase transition-driven collective assembly of gold nanoparticles in a thermotropic liquid crystal. A temperature-induced transition from the isotropic to the nematic phase leads to the assembly of individual nanometre-sized particles into arrays of micrometre-sized aggregates, whose size and characteristic spacing can be tuned by varying the cooling rate. This fully reversible process offers hierarchical control over structural order on the molecular, nanoscopic, and microscopic level and is an interesting model system for the programmable patterning of nanocomposites with access to micrometre-sized periodicities.

scholarly journals Orientational self-assembly of nanoparticles in nematic droplets

2021 ◽  
Author(s):  
Natália Tomašovičová ◽  
Marianna Batkova ◽  
Ivan Batko ◽  
Veronika Lacková ◽  
Vlasta Zavišová ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Self Assembly

The interplay between the anchoring of liquid crystal (LC) molecules at the substrate and at the surface of nanoparticles (NPs) results in an orientational self-assembly of nanoparticles in sessile nematic droplets.

Chiral-induced self-assembly sphere phase liquid crystal with fast switching time

2014 ◽  
Vol 104 (9) ◽  
pp. 091116 ◽  
Author(s):  
Ji-Liang Zhu ◽  
Shui-Bin Ni ◽  
Chao Ping Chen ◽  
Dong-Qing Wu ◽  
Xiao-Long Song ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Self Assembly ◽  
Switching Time ◽  
Fast Switching ◽  
Phase Liquid

A Biological System Producing a Self-Assembling Cholesteric Protein Liquid Crystal

1971 ◽  
Vol 8 (1) ◽  
pp. 93-109
Author(s):  
A. C. NEVILLE ◽  
B. M. LUKE
Keyword(s):  
Liquid Crystal ◽  
Electron Density ◽  
Electron Micrographs ◽  
Self Assembly ◽  
Liquid Crystalline ◽  
Density Variation ◽  
Self Assembling ◽  
The Matrix ◽  
Electron Density Variation ◽  
Helicoidal Structure

The protein in the oothecal glands of praying mantids (Sphodromantis tenuidentata, Miomantis monacha) exists in the form of lamellar liquid crystalline spherulites, which coalesce as they flow out of a punctured gland tubule. Electron micrographs of sections of these spherulites after fixation show parabolic patterns of an electron-light component, set in a continuous matrix of protein. Such patterns arise in helicoidal systems (e.g. arthropod cuticle) and microdensitometric scans of the matrix show a rhythmical electron-density variation consistent with helicoidal structure. Double spiral patterns identical to those seen in liquid crystal spherulites are illustrated. These properties resemble those of cholesteric liquid crystals. The constructional units appear to be molecular rather than fibrillar as described by previous authors. The helicoidal architecture arises by self-assembly in the gland lumen. Lamellar surface structures self-assembled spontaneously on glass coverslips when the protein was left to stand for several days. When heated to 55 °C, the birefringent liquid crystalline protein abruptly changes to an isotropic gel, with associated loss of parabolic patterning in electron micrographs and of the rhythmical electron-density variation on microdensitometric scans. This behaviour is compared to the formation of gelatin from collagen, in terms of the randomization of an originally ordered secondary structure.

Thermally bandwidth-controllable reflective liquid crystal film from rupture and self-assembly of hydrogen bonds

2016 ◽  
Vol 43 (12) ◽  
pp. 1732-1738 ◽  
Author(s):  
Feifei Wang ◽  
Ping Song ◽  
Huai Yang ◽  
Xibin Shao
Keyword(s):  
Liquid Crystal ◽  
Hydrogen Bonds ◽  
Self Assembly ◽  
Crystal Film

scholarly journals Cellulose nanocrystal-based materials: from liquid crystal self-assembly and glass formation to multifunctional thin films

2014 ◽  
Vol 6 (1) ◽  
pp. e80-e80 ◽  
Author(s):  
Jan P F Lagerwall ◽  
Christina Schütz ◽  
Michaela Salajkova ◽  
JungHyun Noh ◽  
Ji Hyun Park ◽  
...  
Keyword(s):  
Thin Films ◽  
Liquid Crystal ◽  
Self Assembly ◽  
Glass Formation ◽  
Cellulose Nanocrystal

scholarly journals Mechanisms of Chiral Transfer in Optically Active Dopant – Nematic Liquid Crystal Systems

2020 ◽  
Vol 20 (4) ◽  
pp. 6-26
Author(s):  
V. A. Burmistrov ◽  
V. V. Aleksandriiskii ◽  
I. V. Novikov ◽  
O. I. Koifman
Keyword(s):  
Liquid Crystal ◽  
Nematic Liquid Crystal ◽  
Self Assembly ◽  
Liquid Crystalline ◽  
High Efficiency ◽  
Stationary Phases ◽  
Theoretical Description ◽  
Optically Active ◽  
Axial Coordination ◽  
Chiral Dopants

Induction of helical mesophases by incorporating chiral dopants into the nematics matrix is the promising modern trends in the chemistry of liquid crystals. This process is associated with a unique phenomenon - an amplification of chirality in liquid-crystalline phases, which ensures the detection of enantiomers by their chiral induction, much more sensitive than other methods. The relevance of this approach is due to the need to create perspective electro-optical devices operating with ultra-low control voltages based on twist effects, chromatographic stationary phases with high chiral selectivity, flexible magnets, photo-sensitive nanostructures, and other smart LC materials. The successful solution of these problems is impossible without experimental research and theoretical comprehension of the mechanisms of third level chiral transfer optically active dopant – nematic liquid crystal. In the last decade, a large number of works have appeared on the solution of these problems. This review is devoted to a generalization of the experimental results and a theoretical description of the transfer of molecular chirality to orientationally ordered systems with the participation of both chiral molecular substituents with an asymmetric carbon atom and planar or quasi-planar fragments chirally distorted relative to each other. The stereochemical aspects of induction associated with the structural correspondences of the dopant and nematic liquid crystal, as well as the main classes of optically active additives, are discussed. Application of metal complexes, both Werner and macroheterocyclic, are presented. Special attention is paid to the results of the mechanisms study of chiral transfer due to various intermolecular interactions: hydrogen bonding, axial coordination, and the formation of inclusion compounds. The high efficiency of induction of spiral mesophases has been demonstrated with a combination of different self-assembly mechanisms in liquid crystal - chiral additive systems.

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