Radiative emission from triplet excitations in light emitting devices

Abstract

Using the recently derived time-dependent spin-orbit-photon interaction operator and first order perturbation theoiy the rate of spontaneous radiative emission, from triplet excitations in molecular solids and polymers is calculated within the two-level approximation. The rate depends on the square of the atomic number of the constituting atoms. The calculated rates and corresponding radiative lifetimes agree very well with the known experimental results in conjugated polymers incorporated with platinum atoms. Present results are compared with the known results obtained from the traditional theory for naphthalene and anthracene and found in better agreement with experiments. The traditional theory is briefly reviewed. © 2009 WILEY-VCH Verlag GmbH & Co. KGaA.