摘要
研究了含三苯胺多枝化合物———4 正丁氧基苯乙烯三苯胺(T1)、双(4 正丁氧基苯乙烯)三苯胺(T2)和三(4 正丁氧基苯乙烯)三苯胺(T3)溶液的光谱行为.结果发现:在三苯胺对位进行单枝化(T1)、双枝化(T2)和三枝化(T3)后,摩尔吸光系数增大且最大吸收波长红移,但红移幅度依次减小,表明经多枝化处理后分子能带带隙趋于接近.在不同的溶剂中,T1—T3荧光行为有所不同:在环己烷中相对荧光强度的顺序为T3>T2>T1;随着溶剂极性增大,荧光强度顺序发生反转,为T1>T2>T3.量子产率数值(Φf)表明,随着溶剂的极性增大,T1和T2、T3的量子产率变化顺序也不同:T1的Φf值随溶剂极性的增大而增大,而T3的Φf值则基本是随着溶剂极性的增大而依次减小.造成这种差别的原因可能是ICT和TICT两发光态在极性不同的溶剂中相互转化、平衡移动所致.
Optical physical properties of three new chromophores with triphenylamine as molecular frame-work bearing one,two,and three 4-(n-bytyloxy-styryl) group(s) at the periphery respectively,(named as T1,T2,and T3) have been investigated.It is interesting to find,on the one hand,that the relative fluorescence intensity is increased from T1 to T2 and to T3 in nonpolar solvents,but decreased from T1 to T2 and to T3 in polar solvents.On the other hand,fluorescence quantum yields for T1 is increased,while those for T3 is decreased with the increase of the solvent polarity,which means that there may exist two emission mechanism,i.e.ICT state and TICT state functioning in different solvents.Although the mole absorbance (ε) is increased monotonously from T1 to T2 and to T3 in any solvents used,maximum absorption wavelengths and corresponding absorption edge are red-shifted from T1 to T2 and to T3,however,the shift span for T3 is almost negligible,suggesting that the energy gap may remain unchanged when further dendritical structure is formed.
出处
《感光科学与光化学》
SCIE
EI
CAS
CSCD
北大核心
2004年第1期4-12,共9页
Photographic Science and Photochemistry
基金
国家自然科学基金(50273024)
江苏省自然科学基金(BK2002041)
江苏省教委自然科学基金(02KJB430001)
