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A unique gyroid cubic phase has been discovered for a discotic star mesogen with three covalently attached DNA bases. In this cubic Ia3‾d ${Ia\bar{3}d}$ phase, the conjugated core of the mesogens and the thymine pseudo guests self‐assemble in mirror image continuous networks, representing a semiconducting material with three‐dimensional transport pathways. The hole carrier mobilities are found to be in the typical range of poly(phenylenevinylene) scaffolds. This structure is stabilized by a weak hydrogen bonding between the thymine bases and can be switched to a columnar liquid crystal – thermally and by the addition of complementary adenine guests. [ABSTRACT FROM AUTHOR]

Sterically crowded, shape-persistent star mesogens with three oligophenylenevinylene arms provide free space in which Blatter radical guests are incorporated by covalent bonds (esters) or supramolecular interactions (hydrogen bonds). The radical guests transform these compounds to paramagnetic liquid crystalline (LC) materials. The LC molecules are demonstrated to self-assemble into several types of columnar phases, a process that is controlled by the binding mode and the size of the star mesogen cavity. The conjugated scaffold remains stable in the presence of these radicals. Magnetic investigations by means of solid-state VT-EPR and SQUID experiments reveal that these materials are paramagnetic with weak antiferromagnetic interactions. In contrast to the covalent mesogens, the supramolecular systems do not only possess much lower clearing temperatures, but also radical guests exhibit mobility independent of the phase transition leading to soft paramagnetic materials with tunable magnetic properties. [ABSTRACT FROM AUTHOR]

The self‐assembly of umbrella‐shaped mesogens is explored with subphthalocyanine cores and oligo(thienyl) arms with different lengths in the light of their application as light‐harvesting and photoconducting materials. While the shortest arm derivatives self‐assemble in a conventional columnar phase with a single mesogen as a repeating unit, the more extended derivatives generate dimers that pile up into liquid crystalline columns. In contrast to the antiparallel arrangement known from single crystals, the present mesogens align as parallel dimers in polar columnar phases as confirmed by X‐ray scattering, experimental densities, dielectric spectroscopy, second harmonic generation, alignment, and conductivity studies. UV–vis and fluorescence spectroscopies reveal a broad absorption in the visible range and only weak emission of the Q‐band. Thus, these light‐collecting molecules forming strongly polar columnar mesophases are attractive for application in the area of photoconductive materials. [ABSTRACT FROM AUTHOR]