The columnar phase is a class of liquid-crystalline phases in which molecules assemble into cylindrical structures to act as mesogens. Originally, these kinds of liquid crystals were called discotic liquid crystals because the columnar structures are composed of flat-shaped discotic molecules stacked one-dimensionally. Since recent findings provide a number of columnar liquid crystals consisting of non-discoid mesogens, it is more common now to classify this state of matter and compounds with these properties as columnar liquid crystals. Schlieren texture of Liquid Crystal nematic phase Liquid crystals are substances that exhibit a phase of matter that has properties between those of a conventional liquid, and those of a solid crystal. ... Mesogen is the fundamental unit of a liquid crystal that induces structural order in the crystals. ...

Classes of Columnar Phases

Columnar liquid crystals are grouped by their structural order and the ways of packing of the columns. Nematic columnar liquid crystals have no long-range order and are less organized than other columnar liquid crystals. Other columnar phases with long-range order are classified by their two-dimensional lattices: hexagonal, tetragonal, rectangular, and oblique phases. To meet Wikipedias quality standards, this article or section may require cleanup. ...

The discotic nematic phase includes nematic liquid crystals composed of flat-shaped discotic molecules without long-range order. In this phase, molecules do not form specific columnar assemblies but only float with their short axes in parallel to the director (a unit vector which defines the liquid-crystalline alignment and order).

Current Topics of Interest

The first discotic liquid crystal was found in 1977 by the Indian researcher Sivaramakrishna Chandrasekhar. This molecule has one central benzene ring surrounded by six alkyl chains. Since then, a large number of discoid mesogenic compounds have been discovered in which triphenylene, porphyrin, phthalocyanine, coronene, and other aromatic molecules are involved. The typical columnar liquid-crystalline molecules have a pi-electron-rich aromatic core attached by flexible alkyl chains. This structure is attracting particular attention for potential molecular electronics in which aromatic parts transport electrons or holes and alkyl chains act as insulating parts. The advantages of liquid-crystalline conductors are their anisotropy, processability, and self-healing characteristics for structural defects. For the album by Ash, see 1977 (album). ... Benzene, also known as benzol, is an organic chemical compound with the formula C6H6. ... An alkane is an acyclic saturated hydrocarbon. ... Mesogen is the fundamental unit of a liquid crystal that induces structural order in the crystals. ... In chemistry, triphenylene is the name of an organic compound. ... Core porphyrin structure 3D representation A porphyrin is a heterocyclic macrocycle made from 4 pyrrole subunits linked on opposite sides (α position) through 4 methine bridges (=CH-). The macrocycle, therefore, is more aromatic than the related corrins, chlorins (2,3-dihydroporphyrin) and bacteriochlorins (2,3,12,13-tetrahydroporphyrin). ... This article needs to be cleaned up to conform to a higher standard of quality. ... Coronene is an aromatic molecule consisting of 7 benzene rings. ... In chemistry, an aromatic molecule is one in which electrons are free to cycle around circular arrangements of atoms, which are alternately singly and doubly bonded to one another. ...