Table 1. Kinetic data for photoinduced processes of 16+ in deaerated acetonitrile solution in the temperature range 284–303 K.
T, K | ket, s-1 | kbet, s-1 | kptz, liter·mol-1·s-1 | krd, s-1 | τbet, μs | τrd, μs |
---|---|---|---|---|---|---|
284 | 1.5 × 105 (1.8 × 105) | 1.4 × 105 (5.4 × 105) | 7.9 × 108 (5.0 × 108) | 8.1 × 102 | 7.4 (1.8) | 1,230 |
288 | 1.7 × 105 (2.0 × 105) | 1.4 × 105 (5.9 × 105) | 8.4 × 108 (5.0 × 108) | 1.8 × 103 | 7.1 (1.7) | 550 |
293 | 1.7 × 105 (2.1 × 105) | 1.4 × 105 (6.7 × 105) | 7.6 × 108 (4.9 × 108) | 3.5 × 103 | 7.0 (1.5) | 285 |
299 | 1.8 × 105 (2.4 × 105) | 1.4 × 105 (7.0 × 105) | 7.8 × 108 (4.8 × 108) | 1.3 × 104 | 7.1 (1.4) | 78 |
303 | 2.5 × 105 (3.1 × 105) | 1.5 × 105 (6.9 × 105) | 8.1 × 108 (4.8 × 108) | 2.1 × 104 | 6.7 (1.4) | 47 |
The corresponding data for 26+ are reported in parentheses. Subscripts are defined as follows: et, photoinduced electron transfer (Scheme 2a, step 2); bet, back electron transfer (Scheme 2a, steps 5 and 6); ptz, bimolecular electron transfer between the A1+ unit and ptz+ (Scheme 2b, steps 9 and 10); rd, displacement of the ring from A1+ to the A22+ station corresponding to the shift of the transient absorption maximum of the A1+ unit (Scheme 2 a and b, step 4).