Hexasubstituted C3-symmetric benzenes with three elongated shape-persistent oligo(phenylenevinylene) arms and three pyridyl hydrogen bond acceptors have been synthesized. These mesogens assemble in a double helical columnar liquid crystal (LC) structure, owing to the compensation of free spaces between conjugated arms by dimer formation. The void is filled also by up to three anthracene carboxylic acids as guests forming hydrogen bonded supermesogens assembling in columnar LC and soft crystal phases. Thin film fluorescence and solid-state NMR spectroscopy imply a transition from a disordered columnar LC to an unexpected double nanosegregated morphology of a filled soft columnar crystal phase. Here occurs an additional intracolumnar separation of anthracene and oligo(phenylenevinylene) chromophores, besides the general segregation of aliphatic and aromatic building blocks in LC structures. The new type of supermesogens will enable the rational design of host-guest double cables with a wide range of different conjugated building blocksrmation of aligned thin films and thus for potential applications.
Matthias Lehmann, Philipp Maier, Matthias Grüne
Chemistry-A European Journal
complex networks, complex systems, computational finance