本論文利用實驗室自行架設的飛秒瞬態吸收(transient absorption, TA)光譜儀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。研究對象為以苯(benzene)為電子給體，四氰基乙烯(tetracyanoethylene)為電子受體之EDA錯合物溶於不同比例之苯/二氯甲烷混合溶劑。在論文中，我們直接激發Bz/TCNE錯合物的電荷轉移(charge transfer, CT)態，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，並與實驗室前人研究激發溶於不同比例苯/四氯化碳混合溶劑的Bz/TCNE錯合物的CT態電子轉移動力學做比較。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。我們發現電荷再結合過程的時間常數在二氯甲烷溶劑中比在四氯化碳溶劑中來的短，且此時間常數隨著苯/二氯甲烷混合溶液中苯的比例的變化趨勢與前人所報告之在苯/四氯化碳混合溶液中的結果有所不同。

In this thesis we study the charge-transfer (CT) dynamics of the electron donor-acceptor (EDA) complexes with a home-built broadband femtosecond transient absorption (TA) spectrometer. The EDA system studied here are benzene/tetracyanoethylene (Bz/TCNE) complexes dissolved in a series of Bz/Dichloromethane (Bz/DCM) cosolvents of different ratios. We directly excite the CT state of Bz/TCNE complexes in dichloromethane to observe their relaxation dynamics and compare the results with those of previously-studied Bz/TCNE complex in carbon tetrachloride. We observe spectral characteristics of TCNE radical anion (TCNE-) and benzene dimer radical cation ((Bz)2+). By analyzing their time-dependent behaviors, we found that after exciting the CT state of Bz/TCNE complexes, the excited state undergoes rapid solvation and vibrational relaxation, followed by a slower charge recombination (CR) reaction. We found that the time constant of the CR process is shorter in the dichloromethane solvent than in the carbon tetrachloride solvent. The variation of the CR time constant with the benzene ratio in the Bz/DCM cosolvents is different from that observed in Bz/CCl4 cosolvents.

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