物理化学学报 >> 1999, Vol. 15 >> Issue (07): 636-642.doi: 10.3866/PKU.WHXB19990711

研究论文 上一篇    下一篇

酞菁和卟啉分子的超快内转换和振动弛豫

何勇, 熊轶嘉, 朱起鹤, 孔繁敖   

  1. 中国科学院化学研究所 分子反应动力学国家重点实验室,北京 100080
  • 收稿日期:1998-11-17 修回日期:1999-02-04 发布日期:1999-07-15
  • 通讯作者: 孔繁敖

Ultrafast Internal Conversion and Vibrational Relaxation of Butylphthalocyanine and Tetraphenylporphyrin in Solution

He Yong, Xiong Yi-Jia, Zhu Qi-He, Kong Fan-Ao   

  1. State Key Laboratory of Molecular Reaction Dynamics,Institute of Chemistry,Chinese Academy of Sciences,Beijing 100080
  • Received:1998-11-17 Revised:1999-02-04 Published:1999-07-15
  • Contact: Kong Fan-Ao

摘要:

用微扰密度矩阵和瞬态线性极化率理论,模拟了四特丁基酞菁(BuPc)和四苯基卟啉(TPP)分子的飞秒荧光亏蚀谱.初步定量地确定了它们的Huang-Rhys因子.振动弛豫和电子激发态溶剂化的速率常数.飞秒荧光亏蚀谱在零延时附近的尖峰.归结为S2→S1的内转换所造成的后果.通过对光谱的模拟,比较可靠地确定了内转换速率常数.

关键词: 飞秒荧光亏蚀谱, 超快内转换, 振动弛豫

Abstract:

Ultrafast internal conversion (IC) and vibrational relaxation dynamics of electronically excited butylphthalocyanine (BuPc ) and tetra-phenylporpyrin (TPP ) molecules in solution are theoretically studied on the basis of the perturbative density operaor method and the transient linear susceptibility theory. Femtosecond time-resolved profile of fluorescence depetion is simulated with a single vibrational mode. The internal conversion, the vibrational relaxation and the solvation rate constants in electronically excited states are determined. The results show that the sharp peak of fluorescence depletion reflects primarily the internal conversion process from the S2 state to the S1 state of BuPc and TPP.IC occurs in a 200 fs time scale.

Key words: Femtosecond fluorescence depldtion spectra, Ultrafast internal conversion, Vibrational relxation