The columnar phase is a class of mesophases in which molecules assemble into cylindrical structures to act as mesogens.
Takuzo Aida and co-workers recently reported cyclic peptides that self-assemble into polar columnar organizations.
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).
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.