Mesogenic [Rh(L)4](A) complexes form mesophases with RhI•••RhI-containing and triphenylene-discotic segregated columns. Effect of RhI•••RhI interactions and A- = [Au(CN)2]- on hole mobility

Rh-I complexes [Rh(L)(4)](A) (A(-) = Cl-, BF4-, [Au(CN)(2)](-)) with conventional arylisocyanides (p-MeC6H4(NC), L-A; p-MeOC6H4(NC), L-B; 3,5-(OMe)(2)C6H3(NC), L-C) or with the alkoxy-functionalized triphenylene-arylisocyanides TPh(OC12H25)(5)(O(CH2)(6)OC6H4(NC)-p) (L-D1) and TPh(OC12H25)(5)(O(CH2)(6)OC6H2Me2(NC)-p) (L-D2), have been prepared and their self-assembly, aggregation, optical, redox, mesogenic and conducting properties investigated. Intermolecular pi-pi stacking, Rh-I center dot center dot center dot Rh-I, and Rh-I center dot center dot center dot Au-I interactions rule the crystal packing and aggregation in solution for the complexes with L-A, L-B, and L-C. For the Rh-I complexes with the alkoxy-functionalized-triphenylene isocyanides L-D1 and L-D2 mesogenic behaviour is induced, giving rise to multicolumnar mesophases in broad temperature ranges (ca. 70-160 degrees C). Detailed analysis (POM, DSC, SAXS/WAXS and GIWAXS) of the columnar mesophases has allowed us to propose precise packing models that explain the diverse supramolecular arrangements found in the nanostructured condensed phases. Columnar alignments predominantly with Rh center dot center dot center dot Rh interactions (or Rh center dot center dot center dot Au, only for L-D2 in specific conditions) are observed, depending on the aligning conditions. The hole mobility in the columnar mesophases of the complexes with Rh center dot center dot center dot Rh interactions are similar to 1 cm(2) V-1 s(-1), that is up to four orders of magnitude higher than those reported for columnar mesophases of organic triphenylene derivatives, and increases one order of magnitude further in the mesophases containing the [Au(CN)(2)](-) counteranion.