Photophysical Study of New Methanofullerene−TTF Dyads: An Obvious Intramolecular Charge Transfer in the Ground States
作者:Hiroyuki Nishikawa、Shigeru Kojima、Takeshi Kodama、Isao Ikemoto、Shinzo Suzuki、Koichi Kikuchi、Mamoru Fujitsuka、Hongxia Luo、Yasuyuki Araki、Osamu Ito
DOI:10.1021/jp037145n
日期:2004.3.1
Three isomers of a new C 6 0 -TTF dyad-C 6 o -X-TTF (X = ortho, meta, and para)-have been synthesized by changing the linking positions (ortho, meta, and para) at a phenyl group that is attached to the methano-[60]fullerene. The dyads showed clear intramolecular charge transfer (CT) absorption bands in the steady-state absorption spectra, which was indicative of an intramolecular CT interaction between
通过改变苯基的连接位置(邻位、间位和对位)合成了一种新的 C 6 0 -TTF dyad-C 6 o -X-TTF(X = 邻位、间位和对位)的三种异构体与甲烷-[60]富勒烯相连。对子在稳态吸收光谱中显示出清晰的分子内电荷转移 (CT) 吸收带,这表明基态 C 6 0 和 TTF 部分之间存在分子内 CT 相互作用。CT吸收带强度的增加遵循C 6 0 -邻-TTF > C 6 0 -间-TTF >> C 6 0 -对-TTF的顺序,这可以通过计算的优化分子结构来合理解释从头开始级别。观察到来自局部激发的 C 6 0 部分的荧光强度的极端猝灭遵循上述顺序,这表明非常快的激发单重态动力学取决于异构体。还观察到在纳秒区域检测到的 C 6 0 部分的三重态吸收强度的猝灭遵循相同的顺序,这表明存在比系统间交叉更有效的竞争路径。根据亚皮秒瞬态吸收测量,对于 C 6 0 -ortho-TTF(和 C 6