A theoretical study has been conducted on a series of aggregation-induced emission (AIE) type thermally activated delayed fluorescence (TADF) materials 1-4 constructed with the [2.2]paracyclophane framework through combining quantum mechanics and molecular mechanics method. The through-space charge transfer (TSCT) characteristics were demonstrated by the analysis of the frontier molecular orbitals and the fragmental charge transfer component between donor and bridge, donor and acceptor, bridge and acceptor. Calculated results reveal that the spatial conjugation effect leads to greater oscillator strength of some singlet excited states, and when the spin-orbit coupling (SOC) values between them and their respective neighboring triplet states are large, the corresponding intersystem crossing rate will be significantly enhanced. TADF emission properties of the molecules were also analyzed by comparing energy gaps, reorganization energies, and SOC values between the lowest singlet and triplet state in isolated and aggregated environments and the reverse intersystem crossing rates. Then, by comparing the radiative rate and the reorganization energies between S1 and S0 of the molecules in different environments, the enhancing effect of the aggregation environment on the luminescence efficiency of the molecules was demonstrated. Considering all the calculated parameters, we believe that molecules 2 and 4 are potential AIE-type TADF materials.

You have access to this article

Please wait while we load your content... Something went wrong. Try again?