我們研究反式對位苯胺基雙苯乙烯(trans-4-(N-phenylamino)stilbene, p1H)，以及反式對位對苯腈基苯胺基雙苯乙烯(trans-4-(N-(4-cyanophenyl)amino)stilbene, p1CN)之溶劑效應與其光激發態動力學模型。經由穩態吸收/螢光光譜之結果，推算出兩種化合物之激發態偶極矩，p1H之PICT能階為11.3 D，p1CN之PICT為9.3 D，而TICT為16.2 D。而由瞬態吸收光譜之數據可知，p1H與p1CN由330 nm激發到Franck-Condon能階後，會很快的產生電荷轉移變為PICT能階，時間常數約為0.7~1.8 ps，而PICT之緩解機制則在兩種化合物中有所不同，p1H之PICT只會經由放出螢光與光異構化回到基態，時間常數落在10~120 ps之間，隨著溶劑之黏度與極性而變，而p1CN則可經由轉為TICT緩解，TICT生成之時間常數約在5~30 ps之間，隨溶劑之黏度與極性而變，其能障高低隨溶劑之極性增加而降低，但也隨黏度增加而增高。而在不同溶劑下，TICT之生命期τ_3^TICT均比PICT之τ_3^PICT短約25%，表示TICT之電荷重組速率較快，因此推測在p1CN中，扭轉之分子結構可能會增進其電荷重組效率。而根據p1H及p1CN在EtOH中之表現差異來看，在p1CN中，氫鍵造成的效應非常明顯，但p1H則否，暗示了-CN取代基的存在會大幅增益氫鍵造成的內轉換效益。

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