Multiple Hot exciton channel molecular design in organic electroluminescence materials: a theoretical investigation

The Hot exciton channel material can take into account both maximizing exciton utilization efficiency (EUE) and maximizing photoluminescent quantum yield (PLQY). It is a new material with broad application prospects. In this article, starting from the classical D-A molecular model system, the long-range correction functional omega b97x, which can accurately describe the CT state, was selected for the excited state calculation. We extended the D-A system to the X-B-D system. In order to preserve the large Delta ET1-T2, we selected the NZ group as the central core B; we chose a donor group 10H-phenoxazine (X1) and an acceptor group 1,3,4,6,7,9,9b-heptaazap-henalene (X2) as part X, and 10 donors with different HOMO as part D. By simulating the ground state and excited state properties of these 20 molecules, we found that compared with the traditional D-A molecule, the excited state of the X-B-D molecules underwent more CT or HLCT transition; the number of channels for the reverse intersystem crossing increased from one to multiple, which may provide a new idea for the design of new multi-channel Hot exciton materials.

Automated summary

The article explores the excited state properties of X-B-D molecules starting from the classical D-A molecular model system, using the long-range correction functional omega b97x for excited state calculations. It was found that X-B-D molecules undergo more CT or HLCT transitions in excited states compared to traditional D-A molecules, with an increase in the number of channels for reverse intersystem crossing, potentially providing new directions for the design of multi-channel Hot exciton materials.