“…The internal conversion process is dependent on the vibrational wave function overlap associated with a structural reorganization in the excited state, and the increased intersystem crossing rate results primarily from enhanced spin−orbit coupling in the nonplanar complexes. We have shown that the low quantum yield of the fluorescence of 1Zn or 2Zn arises mainly from the increased intersystem crossing rate 2 Fluorescence Data for Viologen-Linked N- Alkylporphyrins and Their Metal Complexes in MeCN under Argon at 25 °C compdλ ex /nmλ em /nmφ f τ f /ns (yield/%) a |
1 | 429 | 687, 745 (sh) | 0.014 | 1.0 (100) |
| | | | 9.0 (100) b |
1H + | 434 | 690, 745 (sh) | 0.014 | 1.0 (100) |
1Na | 447 | 710 | 0.014 | 0.9 (100) |
1Zn | 436 | 668, 732 | 0.011 | 1.6 (100) |
1Mg | 448 | 710 | 0.014 | 0.9 (100) |
1Al | 450 | 715 | 0.014 | 1.0 (100) |
1Si | 450 | 713 | 0.015 | 1.0 (100) |
2 | 429 | 687, 745 (sh) | 0.020 | <0.6 (25), 3.0 (75) |
2Zn | 436 | 669, 730 | 0.0058 | 1.1 (38), 1.9 (62) |
3 | 429 | 687, 745 (sh) | 0.016 | <0.7 (20), 5.1 (80) |
3Zn | 436 | 668, 730 | 0.012 | 1.7 (100) |
6 | 429 | 687, 745 (sh) | 0.0043 | <0.3 (87), 3.0 (13) |
7 | 430 | 689, 745 (sh) | 0.0049 | <0.3 (72), 3.9 (28) |
7Zn | 436 | 668, 730 | 0.0081 | 1.4 (100) |
9 | 430 | 687, 745 (sh) | 0.0049 | <0.7 (90), 3.1 (10) |
10 | 429 | 687, 745 (sh) | 0.0003 | <0.2 (80), 1.2 (20) c |
| | | | 2.0 (70), 9.0 (30) b |
10H + | 434 | 690, 745 (sh) | 0.0028 | <0.7 (100) |
10Na | 447 | 710 | 0.0005 | <0.7 (100) |
10Zn | 436 | 670, 740 (sh) | 0.0006 | <0.2 (8... |
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