Inspecting the Electronic Architecture and Semiconducting Properties of a Rosette-Like Supramolecular Columnar Liquid Crystal

Chemistry. 2018 Nov 27;24(66):17459-17463. doi: 10.1002/chem.201804748. Epub 2018 Oct 31.

Abstract

Computational and experimental studies unravel the structural and electronic properties of a novel supramolecular liquid crystal built through a hierarchical assembly process resulting in an H-bonded melamine rosette decorated with peripheral triphenylenes. The six-fold symmetry of the mesogen facilitates the formation of a highly organized hexagonal columnar mesophase stable at room temperature. X-ray diffraction and electron density maps confirm additional intra- and intercolumn segregation of functional subunits, and this paves the way for 1D charge transport. Indeed, hole mobility has been measured and found to be higher than for related mesogens. DFT calculations of HOMO and LUMO levels and parameters such as reorganization energy and transfer integral of the rosette structure have been achieved, and not only validate the columnar organization but also establish the way it translates into a favorable electronic architecture and molecular orbital interactions to promote charge carrier mobility.

Keywords: DFT; charge transport; hydrogen bonds; liquid crystals; self-assembly.