Table 2. Antenna-to-ion energy transfer efficiencies (η sens) of Eu(iii) complexes calculated on the basis of the observed emission spectrum, the observed luminescence life-time (τ obs) and the experimental overall luminescence quantum yield (Φ tot) upon ligand excitation (λ ex = 279 nm). τ R is the radiative life-time calculated using eqn (3) (see EP). ΦLnLn is found using eqn (4) (see EP) measured in CH3CN and CH3OH.
| Complex | τ obs, ms | Φ tot, % | τ R, ms | Φ Ln Ln , % | η sens, % | Solvent/c, M |
| Eu(1(R))3 | 1.86 ± 0.02 | 2.1 ± 0.1 | 6.43 ± 0.04 | 28.94 ± 0.01 | 7.26 ± 0.02 | CH3CN 2.72 × 10–5 M |
| Eu(1(S))3 | 1.86 ± 0.02 | 1.6 ± 0.5 | 6.39 ± 0.04 | 29.13 ± 0.01 | 5.49 ± 0.02 | |
| Eu(5(R))3 | 1.94 ± 0.01 | 8.2 ± 0.3 | 7.13 ± 0.02 | 27.22 ± 0.01 | 30.20 ± 0.03 | |
| Eu(5(S))3 | 1.94 ± 0.01 | 8.4 ± 0.3 | 7.18 ± 0.04 | 27.02 ± 0.03 | 30.90 ± 0.01 | |
| Eu(1(R))3 | 0.58 ± 0.01 (18.8%) | 0.6 ± 0.1 | — | — | — | CH3OH 5.79 × 10–5 M |
| 1.95 ± 0.01 (81.2%) | ||||||
| Eu(1(S))3 | 0.58 ± 0.01 (18.8%) | 0.5 ± 0.1 | — | — | — | |
| 1.95 ± 0.01 (81.2%) | ||||||
| Eu(5(R))3 | 0.58 ± 0.01 (79.0%) | 2.2 ± 0.2 | — | — | — | |
| 1.76 ± 0.03 (21.0%) | ||||||
| Eu(5(S))3 | 0.57 ± 0.01 (81.0%) | 2.3 ± 0.1 | — | — | — | |
| 1.58 ± 0.01 (19.0%) | ||||||
| 0.57 ± 0.01 (81.0%) |