Table 1. UV-visible and fluorescence data for H22 and [Et42][PF6]2 at 298 K. Concentrations ca. 2 × 10–5 M.
| Compound/solvent | Salt added | λ abs/nm (ε/10–4 M–1 cm–1) | λ em (nm) |
| H22/H2O | No salt | 206 (74.9), 220 (71.4), 243 (60.9), 271 (78.0), 457 (19.1) | 594 |
| [Et42][PF6]2/MeCN | No salt | 207 (75.5), 245 (71.2), 272 (79.9), 380 (13.7), 449 (16.8) | 635 |
| 0.01 M NaClO4 | 207 (75.5), 245 (70.2), 272 (76.3), 381 (13.7), 449 (16.9) | 636 | |
| 0.01 M Mg(ClO4)2 | 206 (84.0), 246 (75.5), 272 (91.7), 379 (14.5), 449 (16.4) | 642 | |
| 0.01 M NBu4PF6 | 207 (77.3), 246 (78.2), 272 (98.5), 380 (13.8), 449 (16.9) | 635 |