Table 2. Picosecond-resolved fluorescence transient lifetime.
| Fluorescence transient lifetime | System | τ1 (ns) | τ2 (ns) | τ3 (ns) | τavg (ns) |
|---|---|---|---|---|---|
| CHT-NPA | 0.6 (29.6%) | 5.9 (70.4%) | 4.4 | ||
| CHT-DHI-NPA-Cis | 0.04 (71.5%) | 0.6 (14.7%) | 5.7 (13.8%) | 0.9 | |
| CHT-DHI-NPA-Trans | 0.07 (51%) | 0.6 (31%) | 5.1 (18%) | 1.2 | |
| CHT-PF | 0.4 (16%) | 4.8 (84%) | 4.1 | ||
| CHT-DHI-PF-Cis | 0.3 (29.1%) | 4.5 (70.9%) | 3.3 | ||
| CHT-DHI-PF-Trans | 0.067 (40.5%) | 1.0 (32.4%) | 4.6 (27.1%) | 1.6 | |
| FRET parameters | J (λ) | R0(Å) | Efficiency | rDA (nm) | |
| CHT-DHI-NPA-Cis | 1.426 × 1014 | 31.1 | 79.3 | 2.5 | |
| CHT-DHI-PF-Trans | 0.488 × 1015 | 35.56 | 61.2 | 3.3 |
The emission (monitored at 450 nm for NPA systems and at 520 nm for PF systems) was detected using an excitation laser at 375 nm. Numbers in parentheses indicate relative contributions. The reported lifetimes carry ~5% uncertainties.