Table 3.
Calculated spectral properties of 3, 4 and 8, based on spectral data.
| Comp./Medium | ES1(kJ mol−1) | f | τ0(ns) | τF-calc(ns) | kF-calc(109 s−1) | knr-calc(109 s−1) |
|---|---|---|---|---|---|---|
| 3 | ||||||
| MeOH | 258 | 0.33 | 8.5 | 3.4 | 0.12 | 0.18 |
| CHCl3 | 263 | 0.34 | 8.6 | 3.8 | 0.12 | 0.15 |
| PMMA | 261 | 0.31 | 9.3 | 7.5 | 0.11 | 0.03 |
| PVC | 258 | 0.46 | 6.5 | 7.0 | 0.15 | - |
| PS | 264 | 0.29 | 1.0 | 0.2 | 0.99 | 3.57 |
| 4 | ||||||
| MeOH | 256 | 0.34 | 8.3 | 5.3 | 0.12 | 0.07 |
| CHCl3 | 259 | 0.45 | 6.2 | 3.0 | 0.16 | 0.17 |
| PMMA | 267 | 0.38 | 7.4 | 8.0 | 0.14 | - |
| PVC | 253 | 0.44 | 6.6 | 7.3 | 0.15 | - |
| PS | 265 | 0.51 | 5.5 | 1.4 | 0.18 | 0.54 |
| 8 | ||||||
| MeOH | 282 | 0.61 | 3.4 | 0.02 | 0.29 | 45.0 |
| CHCl3 | 284 | 0.36 | 5.9 | 0.06 | 0.17 | 15.0 |
| PMMA | 285 | 0.25 | 8.5 | 2.51 | 0.12 | 0.3 |
| PVC | 283 | 0.47 | 4.6 | 1.32 | 0.22 | 0.5 |
| PS | 285 | 0.29 | 7.3 | 0.43 | 0.14 | 2.2 |
ES1: energy of the singlet state S1 , as 11.96°104 / [( λA + λF )/2], i.e., from the intersection of the normalized fluorescence and absorption spectra, f: oscillator strength given as 4.32 ° 10−9 ∆ν1/2εmax, τ0: natural radiative lifetime of the excited singlet state, τF-calc: calculated fluorescence lifetime as τF-calc= τ0ΦF, kF-calc: calculated natural radiative decay rate constant for the excited singlet state as ΦF/τF-calc, knr-cal: calculated nonradiative decay rate constant for the excited singlet state as (1 − ΦF)/τF-calc.