shown to accurately predict the excited state energies of MR-TADF compounds, including the structurally related DiDOBNA-N. The geometry in the ground state and the HOMO/LUMO levels were calculated at the PBE0/6-31G(d,p) level. As shown in Figure , the LUMO is mostly localized on the DiKTa moieties, while the HOMO is delocalized across the whole molecule.