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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 I a 3 ‾ 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., (© 2023 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

Shape-persistent conjugated mesogens with oligothiophene arms of different lengths have been synthesized. Such mesogens possess free intrinsic space between their conjugated arms. They form columnar liquid-crystalline phases, in which the void is filled by dense helical packing in the neat phase similar to an oligo(phenylene vinylene) derivative of equal size. The void can also be compensated by the inclusion of the small acceptor molecule 2,4,7-trinitrofluorenone. In solution, the acceptor interacts with the core as the largest π-surface, while in the solid material, it is incorporated between the arms and sandwiched by the star-shaped neighbours along the columnar assemblies. The TNF acceptors are not nanosegregated from the star-shaped donors, thus the liquid crystal structure converts to a nano-reservoir for TNF (endo-receptor). These host-guest arrangements are confirmed by comprehensive X-ray scattering experiments and solid-state NMR spectroscopy. This results in ordered columnar hexagonal phases at high temperatures, which change to helical columnar mesophases or to columnar soft crystals at room temperature., (© 2020 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)