The molecular orbitals of the CBN ribbons exhibit similarities with the orbitals of a variety of BNsubstituted aromatic compounds which were synthesized and spectroscopically explored by Hatakeyama and coworkers. The spectroscopic properties of linearly extended Hatakeyama-type BN-doped compounds, denoted BxNy, were recently studied with TDDFT and with wave-function based methods by Pu et al. We selected the compound B2N1 of The structure of B2N1 is shown in Scheme 3. As for the CBN ribbons, the S1 and T1 excited states of the BxNy compounds are of HOMO-LUMO character. The HOMO and LUMO of B2N1 are displayed in Fig. . The spectroscopic data for B2N1 obtained with the ADC(2) method are listed in Table . The corresponding CC2 results can be found in Table . The comparison of 3 (CBN_2-2) and Table (B2N1) reveals that B2N1 exhibits higher vertical S1 and T1 excitation energies and a larger ΔST, while the oscillator strengths are comparable. Due to the significantly smaller ΔST, CBN_2-2 can be expected to be a better TADF emitter than B2N1.