On the Determination of Transition-Moment Directions from Emission Anisotropy Measurements

Abstract

Based on the theory of photoluminescence polarization, a description of the determination of transition-moment directions in luminescent molecules oriented in a stretched polymer film is given. This method is applied to the linear trans-diphenylpolyenes (C2h symmetry): 1,8-diphenyl-octatetraene (DPO), 1,6-diphenylhexatriene (DPH) and 1,4-diphenylbutadiene (DPB). The same transition moment polarized along the long axis of DPO, DPH and DPB is responsible for absorption and fluorescence (B ≈0), when exciting in the long wave absorption band. The results are compared with relevant data obtained from dichroism measurements. © 1986, Walter de Gruyter. All rights reserved.