Abstract:

A comprehensive theoretical model, based on the quantitative energy transfer theory (Förster and Dexter theories) and accurate electronic structure calculations at the CASPT2//CASSCF level was introduced to account for the mechanism of photophysics and tunable emission for Pt-4 and FPt, which are two of promi-sing phosphors for organic light-emitting diodes(OLEDs). For a larger intermolecular distance, the energy tranfer rate is not competitive with the radiative transition, and the blue emission becomes the predominant channel. When the distance decreases to the typical value in the dimer, the energy transfer rate exceeds that of the blue emission and reproduces highly efficient red emission. At the intermediate distance, the blue and red emissions could reach a balance, which results in a mixing white emission.

Key words: Single-dopant white organic light-emitting diode, Complete active space second-order perturbation//complete active space self-consistent field method(CASPT2//CASSCF), Metal-to-ligand charge transfer, Fö, rster and Dexter models for energy transfer