Spectroscopic Study of Organic Light-emitting Polymers: A Review

Abstract

In this review paper, we theoretically investigate the optical properties of the organic light-emitting polymer (OLEP) Despite of its enormous size, OLEP is described well by the oligomer model because of the imperfect backbone structure. By using the molecular exciton theory, we calculate the energy level of S(1) states and Huang-Rhys factor of oligomer which decrease with its chain length The spectral profiles for oligomer thus can be readily calculated and used to explain the absorption and PL for OLEP in dilute solution with a chain length distribution described by a Gaussian function Moreover we show that the luminescence of OLEP in high concentration solution as well as thin film is mainly contributed by the interchain states In the ultrafast time-resolved PL spectrum, we propose a model in which the dynamic processes such as energy transfer, charge transfer, and vibrational relaxation are treated in an equal-footing manner, and find that in the high energy region the states in a thin film of OLEP is dominated by the intrachain species In addition, we discuss the nonradiative transitions occurring in OLEP