Interestingly, the nucleobase structure has little effect on the reduction onsets and LUMO values in the TBT series demonstrating that the LUMO is dominated by the strong BTD acceptor. Although compounds within families 1 and 2 have similar electrochemically derived HOMO–LUMO gaps (ΔEg = 1.77–1.91 eV for 1a–d; ΔEg = 2.29–2.35 eV for 2a–d), the members differ slightly in their HOMO and LUMO values speaking to optical and electronic tunability.