Electrochemical potentials are reported versus a saturated calomel electrode. The reduction potentials (Ered), determined from the DPV peak values, are -1.39 V (DMACBP), -1.22 V (DMACPyBP), -1.33 V (DMACBPN) and -1.11 V (DMACPyBPN), respectively, reflecting the expected anodic shift associated with increasing acceptor strength that is mirrored in the trend of the calculated LUMO levels from BP < BPN < PyBP < PyBPN (Figure ). The calculated LUMO energies are -2.94 eV, -3.12 eV, -3.00 eV and -3. The UV-Vis absorption spectra of the four emitters in dilute toluene are shown in Error! Reference source not found. 3b. The spectra show two prominent spectra features, with two intense bands centered at ~390 nm and a hypochromic broad band at ~470 nm, which are assigned to locally excited (LE) π-π* transitions of the donors and acceptor moiety, and intramolecular charge transfer (ICT) transitions from the DMAC donor to the acceptor moiety, respectively. The ICT band expectedly shifts to lower energies with the introduction of an increasing number of N atoms at positions 4/5 of the acceptor; for instance, the ICT band at 465 nm of DMACBPN (ε = 2.5×10 3 M -1 cm -1 ) is red-shifted compared to that of DMACBP (labs = 458 nm, ε = 1.8×10 3 M -1 cm -1 ) while those of DMACPyBP and DMACPyBPN absorb at essentially the same energy at 474 and 475 nm (ε = 3.2 ×10 3 M -1 cm -1 for both), which match well with the TD-DFT calculated S1 energies (Figure ). Positive photoluminescence (PL) solvatochromism is observed for all compounds (Error! Reference source not found.S29, Table ), which is consistent with the ICT nature of the emissive excited state.