Photophysical properties of a new class of discotic liquid crystalline compounds: Hexa (dodecyl) hexa peri benzyl coronene
Biasutti, MA × Rommens, J Vaes, A De Feyter, Steven De Schryver, FD Herwig, P Mullen, K #
Bulletin des Sociétés Chimiques Belges vol:106 issue:11 pages:659-664
The photophysical properties of hexa (dodecyl) hexa peri benzyl coronene (HBC12), which displays a hexagonal columnar mesophase in a broad temperature domain, have been studied in solution by steady state and time-resolved spectroscopy. These results have been compared with hexa (tertiary butyl) hexa peri benzyl coronene (HBC4) which does not show any liquid crystalline properties. The broadening of the stationary state absorption and fluorescence spectra of HBC12, upon increasing the concentration, suggests the formation of aggregates, which is in line with the multi exponential fluorescence decay of HBC12, observed with time resolved fluorescence experiments. Comparison with the non aggregating HBC4 allowed to attribute the longest decay time to the monomer species. The relative contribution of the short decay times in HBC12 increases as a function of the concentration and the emission wavelength, which suggests that these decays are the result of an ensemble of aggregated species.