本論文利用實驗室自行架設的飛秒瞬態吸收光譜儀(transient absorption, TA)及一套全自動數據擷取電腦程式，研究電子給體-受體(electron doner-acceptor, EDA)錯合物的分子間電子轉移動力學行為。具體研究對象為苯/四氰基乙烯(benzene/tetracyanoethylene, Bz/TCNE)錯合物溶於不同比例苯/四氯化碳混合溶劑。本論文分為兩個主題，第一個是觀察直接激發Bz/TCNE錯合物的電荷轉移(charge transfer, CT)態後的電子轉移動力學；第二個是研究激發Bz/TCNE錯合物中的TCNE至局部激發(locally excited, LE)態後所進行電子轉移動力學。在第一個主題中，我們觀察到四氰基乙烯自由基陰離子(TCNE-)與苯二聚體自由基陽離子((Bz)2+)的光譜特徵，及其時間變化之行為，並與過去本實驗室利用光學克爾光閘超快時間解析螢光光譜(time-resolved fluorescence,TRFL)研究Bz/TCNE錯合物的CT態動力學比較。於TA光譜中，我們觀察到激發錯合物CT態後，激發態錯合物會先進行較快的溶劑及振動緩解，接著為較慢的電荷重合(charge recombination, CR)反應。溶劑與振動緩解時間常數與使用TRFL技術得到的相近(分別約為0.2與8 ps)，(Bz)2+的生成速率隨苯濃度降低而有顯著的下降，與TRFL技術得到結果相近，CR過程則隨著苯濃度由xBz=0.05上升至1，其時間常數由240 ps縮短為100 ps，此趨勢雖與TRFL偵測結果類似，但TA得到的時間常數明顯較TRFL結果為長，在論文中提出許多原因來解釋這個現象。在第二個主題中，我們藉由第一個主題得到的光譜協助指認Bz/TCNE錯合物的離子激發態光譜，並提出一個近似的動力學模型來描述激發Bz/TCNE錯合物LE態後，經由電子轉移生成Bz/TCNE離子激發態錯合物以及其後續衰減動力學。我們觀察到Bz/TCNE錯合物電子轉移速率時間常數約為0.1至0.3 ps(隨苯濃度下降而變長)，為非常快的反應。在高苯濃度溶液中因TCNE激發態周圍有足夠的苯分子，使得(Bz)2+的生成速率與電子轉移速率相近。

We study the charge-transfer (CT) dynamics of the electron donor-acceptor (EDA) complexes with broadband femtosecond transient absorption (TA) spectroscopy. The EDA complex studied here are binary (1:1) and ternary (2:1) benzene/tetracyanoethylene (Bz/TCNE) dissolved in a series of Bz/CCl4 cosolvents. The thesis is mainly divided into two topics. In the first topic, we directly excite the CT state of Bz/TCNE complexes to observe their relaxation dynamics and compare the results with those obtained previously using ultrafast time-resolved fluorescence spectroscopy (TRFL) implemented by optical Kerr gating in our laboratory. We observe spectral characteristics of tetracyanoethylene radical anion (TCNE-) and benzene dimer radical cation ((Bz)2+). By analyzing their time-dependent behavior, we find that after exciting the CT state of Bz/TCNE complex, the excited state complex undergoes rapid solvation and vibrational relaxation, followed by a slower charge recombination (CR) reaction. The time constants of the solvation and vibrational relaxation are similar to those obtained with TRFL technique (about 0.2 and 8 ps, respectively). (Bz)2+ formation rate decreases significantly with decreasing benzene concentration, which is similar to these observed in previous TRFL experiment. With TA spectroscopy, we find a positive correlation between Bz concentration and CR rate: when Bz concentration increases from xBz=0.05 to 1, the CR time constant decreases from 240 ps to 100 ps. Althougt similar correlations have been also observed in previous TRFL experiment, the time constant obtained by TA is substantially longer than those obtained by TRFL. We propose a few possibilities to explain this phenomenon. In the second topic, we study the electron transfer kinetics after exciting electron acceptor (TCNE) to the locally excited (LE) state of the Bz/TCNE complexes. We identify the ionic CT state spectra of Bz/TCNE complexes by comparing with those obtained from the first part. An approximate kinetic model is proposed to describe the electron transfer that generates Bz/TCNE ionic CT state complexes after excitation of the Bz/TCNE complex LE state, and its decay kinetics. We observe that the electron transfer time constants of the Bz/TCNE complex are about 0.1 to 0.3 ps, which are very fast reactions. In the high Bz concentration solutions, there are enough Bz molecules surrounding excited TCNE, so that the formation rate of (Bz)2+ is close to the electron transfer rate.

摘要 i
Abstract ii
謝誌 iv
目錄 vi
圖目錄 viii
表目錄 xi

第一章 序論 1
1.1 電子轉移概論 1
1.2 電子轉移理論 3
1.3 EDA錯合物簡介 5
1.4 苯/四氰基乙烯錯合物電子轉移動力學回顧 6
1.5 論文研究目的 7

第二章 實驗系統與技術 9
2.1超快飛秒雷射系統 9
2.1.1 飛秒雷射產生源 10
2.1.2 能量再生放大器 14
2.2 飛秒瞬態吸收光譜 19
2.2.1 原理 19
2.2.2 光路架設 20
2.2.2.1 390 nm激發瞬態吸收光譜 20
2.2.2.2 276 nm激發瞬態吸收光譜 22
2.2.3 瞬態吸收光譜自動化數據擷取系統 23
2.2.4 儀器響應函數 25
2.2.5 瞬態吸收光譜時間延遲校正 26
2.3 實驗藥品與EDA錯合物配置 28
第三章 以飛秒瞬態吸收光譜研究苯/四氰基乙烯電子轉移態電荷轉移動力學 30
3.1 CT態靜態吸收光譜 30
3.2 390 nm 飛秒瞬態吸收空白實驗 33
3.3 CT態瞬態吸收光譜 35
3.3.1 各樣品的瞬態吸收光譜 35
3.3.2 450±10 nm光區瞬態吸收動力學行為研究 42
3.3.3 850±50 nm光區瞬態吸收動力學行為研究 44
3.4綜合討論 49
3.4.1 CT態衰減動力學討論 49
3.4.2時間解析螢光光譜與瞬態吸收光譜結果比較 50
3.4.3不同類型CT態間轉移動力學討論 54

第四章 以飛秒瞬態吸收光譜研究苯/四氰基乙烯局部激發態電荷轉移動力學56
4.1 LE態靜態吸收光譜 56
4.2 動力學模型假設 57
4.3 276 nm激發飛秒瞬態吸收空白實驗 58
4.4 各樣品以276 nm激發之瞬態吸收光譜 62
4.4.1 各樣品的瞬態吸收光譜 62
4.4.2 455±25 nm光區瞬態吸收動力學行為研究 70
4.4.3 850±50 nm光區瞬態吸收動力學行為研究 74
4.5 綜合討論 77

第五章 結論 81

附錄 83
附錄一 390 nm激發動力學模型擬合過程 83
附錄二 276 nm激發動力學模型擬合過程 84

Reference 86

1. Sit, P. H. L.; Cococcioni, M.; Marzari. N., Phys. Rev. Lett. 2006, 97 (2).
2. Fukuzumi, S., Org. Biomol. Chem. 2003, 1 (4), 609-602.
3. Barbara, P. F.; Meyer, T. J.; Ratner, M. A., J. Phys. Chem. 1996, 100 (31), 13148-13168.
4. Kuznetzov, A. M.; Ulstrup, J., Electron Transfer in Chemisry and Biology：an introduction to the theory. Wiley series in Theoretical Chemistry, 1999.
5. Taube, H., Electron Transfer Reactions in Solution. Academic：New York, 1970.
6. Sit, P. H. L.; Cococcioni, M.; Marzari. N., Phys. Rev. Lett. 2006, 97 (2).
7. Weller, A., Pure Appl. Chem. 1982, 54 (10), 1885-1888.
8. Rehm, D.; Weller, A., Isr. J. Chem. 1970, 8 (2), 259-271.
9. Chakraborty, A.; Chakraborty, D.; Hazra, P.; Seth, D.; Sarkar, N., Chem. Phys. Lett. 2003, 382 (5-6), 508-517.
10. Ghosh, S.; Mondal, S. K.; Sahu, K.; Bhattacharyya, K., J. Phys. Chem. A 2006, 110 (49), 13139-13144
11. Morandeira, A.; Fürstenberg, A.; Pagès, S.; Lang, B.; Vauthey, E., Spectrum 2004, 17 (4).
12. Marcus, R. A., J. Chem. Phys. 1956, 24 (5), 966–978.
13. Kroon, J.; Oevering, H.; Verhoeven, J. W.; Warman, J. M.; Oliver, A. M.; Paddon-Row, M. N., J. Phys. Chem. 1993, 97, 5065–5069.
14. Miller, J. R.; Calcaterra, L. T.; Closs, G. L., J. Am. Chem. Soc. 1984, 106 (10), 3047–3049.
15. Mulliken, R. S., J. Phys. Chem. 1952, 56 (7), 801–822.
16. Chiu, C. C.; Hung, C. C.; Cheng, P. Y., J. Phys. Chem. B, 2016, 120, 12390-12403.
17. Chiu, C. C.; Hung, C. C.; Chen, C. L.; Cheng, P. Y., J. Phys. Chem. B, 2013, 117, 9734-9756.
18. Smith, M. L.; Mchale, J. L. , J. Phys. Chem. 1985, 89, 4002–4007
19. Merriam, M. J.; Rodriguez, R.; Mchale, J. L., J. Phys. Chem. 1987, 91, 1058– 1063
20. Ho, Y. E.; Thompson, C. C. , J. Chem. Soc., Chem. Commun. 1973, 609– 610
21. Foster, R.; Kulevsky, N., J. Chem. Soc., Faraday Trans. 1 1973, 69, 1427– 1431
22. Mukherjee, A.; Lavery, R.; Bagchi, B.; Hynes, J. T., J. Am. Chem. Soc., 2008, 130 (30), 9747-9755.
23. Bloch-Mechkour, A.; Bally, T., Phys. Chem. Chem. Phys. 2015, 17, 10624– 10629
24. Wynne, K.; Galli, C.; Hochstrasser, R. M., J. Chem. Phys. 1994, 100 (7), 4797-4810
25. Lorenc, M.; Ziolek, M.; Naskrecki, R.; Karolczak, J.; Kubicki, J.; Maciejewski, A., Appl. Phys. B 2002, 74, 19-27
26. Jeanmaire, D.L.; Suchanski, M.R.; Van Duyne, R. P., J. Am. Chem. Soc. 1975, 97(7), 1699-1707
27. Inokuchi, Y.; Naitoh, Y.; Ohashi, K.; Saitow, K.C.; Yoshihara, K.; Nishi, N., Chem. Phys. Lett. 1997, 269, 298-304
28. Das, T.N., J. Phys. Chem. A 2009, 113, 6489–6493
29. Piacente, G.; Amadei, A.; D'Abramo, M.; Daidonea, I.; Aschi, M., Phys. Chem. Chem. Phys. 2014, 16, 20624-20638
30. Rumble, C.A.; Vauthey, E., Phys. Chem. Chem. Phys. 2019, 21, 11797-11809