Table 1. Photophysical and Computational Data.
| λabsa (nm) | λema (nm) | Φflb (%) | EHOMOc (eV) | ELUMOc (eV) | Egapd (eV) | ETDDFTe (eV) | Egap(opt)f (eV) | |
|---|---|---|---|---|---|---|---|---|
| Cz–Cz | 341 | 490 | 42 | –5.39 | –1.88 | 3.51 | 3.10 | 3.53 |
| Cz–BMes | 329 | 485 | 36 | –5.35 | –1.85 | 3.50 | 3.12 | 3.45 |
| Cz–Npa | 400 | 579 | 29 | –5.27 | –2.48 | 2.79 | 2.54 | 2.90 |
| Cz–NpaBr | 434 | 573 | 24 | –5.30 | –2.68 | 2.62 | 2.37 | 2.68 |
| Pz–Pz | 356 | N/A | N/A | –5.01 | –1.92 | 3.09 | 2.71 | 3.33 |
| Pz–BMes | 327 | 485 | 32 | –4.95 | –1.86 | 3.09 | 2.73 | 3.45 |
| Pz–Npa | 444 | 581 | 26 | –4.87 | –2.50 | 2.37 | 2.11 | 2.65 |
| Pz–NpaBr | 489 | 625 | 22 | –4.90 | –2.70 | 2.20 | 1.95 | 2.44 |
a
Recorded in CH2Cl2 (c = 1.0 × 10–5 M) for the longest λmax.
b
Fluorescence quantum efficiency (Φfl).
c
Obtained by DFT calculations (B3LYP, 6-31G*).
d
HOMO–LUMO energy gap: Egap = ELUMO – EHOMO.
e
Vertical excitation of the lowest transition (S0 → S1) calculated by TD-DFT (B3LYP, 6-31G**).
f
Calculated from the experimental absorption onset.