Optical studies of distyrylbenzene single crystals

The optical properties of high quality single crystals of distyrylbenzene (DSB) have been studied. At room temperature the photoluminescence (PL) spectrum is quite broad with quantum yield of 65%. At low temperature the PL spectrum shows many narrow vibrational side bands with QE of 68%, where the 0-0 band shows different polarization properties from the other phonon bands. We used the Spano 'pinwheel' model of strong vibration-exciton coupling in herringbone lattice to explain the appearance of the 'forbidden' 0-0 transition at low temperature and its unusual polarization properties. This model also predicts a strong temperature dependence for the 0-0 band relative to the 0-n transitions, as verified experimentally. (C) 2003 Elsevier B.V. All rights reserved.