Da Ros T, Prato M, Guldi D M, Ruzzi M, Pasimeni L
Dipartimento di Scienze Farmaceutiche, Università di Trieste, Italy.
Chemistry. 2001;7(4):816-27. doi: 10.1002/1521-3765(20010216)7:4<816::aid-chem816>3.0.co;2-a.
Photoprocesses associated with the complexation of a pyridine-functionalized C60 fullerene derivative to ruthenium- and zinc-tetraphenylporphyrins (tpp) have been studied by time-resolved optical and transient EPR spectroscopies. It has been found that upon irradiation in toluene, a highly efficient triplet-triplet energy transfer governs the deactivation of the photoexcited [Ru(tpp)], while electron transfer (ET) from the porphyrin to the fullerene prevails in polar solvents. Complexation of [Zn(tpp)] by the fullerene derivative is reversible and, following excitation of the [Zn(tpp)], gives rise to very efficient charge separation. In fluid polar solvents such as THF and benzonitrile, radical-ion pairs (RPs) are generated both by intramolecular ET inside the complex and by intermolecular ET in the uncomplexed form. Charge-separated states have lifetimes of about 10 micros in THF and several hundred of microseconds in benzonitrile at room temperature.
通过时间分辨光谱和瞬态电子顺磁共振光谱研究了吡啶官能化的C60富勒烯衍生物与钌和锌四苯基卟啉（tpp）络合相关的光过程。研究发现，在甲苯中照射时，高效的三重态-三重态能量转移控制着光激发态[Ru(tpp)]的失活，而在极性溶剂中，从卟啉到富勒烯的电子转移（ET）占主导。富勒烯衍生物与[Zn(tpp)]的络合是可逆的，并且在[Zn(tpp)]激发后，会产生非常有效的电荷分离。在诸如四氢呋喃（THF）和苄腈等流体极性溶剂中，络合物内部的分子内电子转移和未络合形式的分子间电子转移均会产生自由基离子对（RPs）。在室温下，电荷分离态在THF中的寿命约为10微秒，在苄腈中的寿命为几百微秒。
