Journal ArticleDOI
X-ray studies on the columnar structures of discotic liquid crystals
TLDR
The columnar mesophase as mentioned in this paper is characterized by a structure in which the disc shaped molecules are stacked one on top of the other to form columns, the different columns constituting a two-dimensional lattice.Abstract:
Since the discovery of discotic liquid crystals in 1977 [1] the field has grown rapidly with an estimated 3000 compounds belonging to this category. Generally these compounds have flat or nearly flat cores and surrounded by four to eight long chain substituents. A vast majority of these compounds exhibit the columnar mesophase. This phase is characterized by a structure in which thedisc shaped molecules are stacked one on top of the other to form columns, the different columns constituting a two-dimensional lattice. Several variants of the columnar structure have been identified-upright columns, tilted columns, hexagonal lattice, rectangular lattice, etc. The stacking of the discs within the column could be on the one extreme, liquid-like or on the other have a true long range order. Although X-ray measurements on quite a few compounds exhibiting these different structures have been reported, the temperature dependence of the various structural parameters does not seem to have received much attention. We ...read more
Citations
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Journal ArticleDOI
Tunable columnar mesophases utilizing C2 symmetric aromatic donor-acceptor complexes.
TL;DR: The study of sterically hindered derivatives led to a set of mixtures in which a dramatic and sudden color change was observed upon crystallization of the mesophase due to a phase separation of the component donor and acceptor units.
Journal ArticleDOI
Solid State Optical Properties of 4-Alkoxy-pyridine Butadiene Derivatives: Reversible Thermal Switching of Luminescence
TL;DR: In this article, the synthesis and optical properties of a series of alkoxyphenyl-pyridyl butadiene derivatives in solution and in the solid state are described.
Journal ArticleDOI
The Crystalline State
TL;DR: The first results of the X-ray method dealt with the stereochemistry of the solid state, which always had been nearly impossible to attack with previous methods as discussed by the authors, and this side of the development is by no means neglected in the first volume of the work before us; the title seems adequate because of the preponderant role the crystalline state has played in the great majority of investigations.
Journal ArticleDOI
Strong aggregation and directional assembly of aromatic oligoamide macrocycles.
Yongan Yang,Wen Feng,Jinchuan Hu,Shuliang Zou,Rongzhao Gao,Kazuhiro Yamato,Mark Kline,Zhonghou Cai,Yi Gao,Yibing Wang,Yibao Li,Yanlian Yang,Lihua Yuan,Xiao Cheng Zeng,Bing Gong,Bing Gong +15 more
TL;DR: The persistent nanotubular assemblies contain non-collapsible hydrophilic internal pores that mediate highly efficient ion transport observed with these macrocycles and serve as cylindrical sites for accommodating guests such as metal ions.
Journal ArticleDOI
Cavity-containing, backbone-rigidified foldamers and macrocycles
TL;DR: This Feature Article gives an account for a host of readily available foldamers and macrocycles with well-defined shapes and non-deformable cavities that appeared over the last decade and indicates that the high efficiencies observed for the formation of these macrocycles are due to the folding of the corresponding uncyclized oligomeric precursors of the corresponds macrocycles.
References
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MonographDOI
Handbook of liquid crystals
John W. Goodby,Peter J. Collings,Takashi Kato,Carsten Tschierske,Helen F. Gleeson,Peter Raynes +5 more
TL;DR: In this article, the basic principles of both low and high-molecular weight materials, as well as the synthesis, characterization, modification, and applications of all types of liquid crystals are discussed.
Journal ArticleDOI
The Crystalline State
TL;DR: The first results of the X-ray method dealt with the stereochemistry of the solid state, which always had been nearly impossible to attack with previous methods as discussed by the authors, and this side of the development is by no means neglected in the first volume of the work before us; the title seems adequate because of the preponderant role the crystalline state has played in the great majority of investigations.