卟啉和金属卟啉光学非线性吸收的溶剂影响

Effect of Solvent on Optical Nonlinear Absorption of Porphyrin and Metalloporphyrins

利用波长为532 nm纳秒脉冲激光的z扫描测量装置对四苯基卟啉(TPP)、四苯基卟啉铜(CuTPP)、四苯基卟啉锌(ZnTPP)和四苯基卟啉镍(NiTPP)在氯仿和吡啶溶剂中的非线性吸收进行了测量,采用五能级模型对实验结果进行了分析,获得了在不同溶剂中的基态吸收截面、激发态吸收截面和系间窜跃时间.结果显示,溶剂的变化导致材料基态吸收光谱改变的同时,也影响材料的非线性吸收参数.通过对三种金属四苯基卟啉比较发现,不同的金属卟啉在氯仿和吡啶溶剂中非线性吸收的表现也不相同.溶剂对卟啉和金属卟啉的光学非线性有着较大的影响.

The nonlinear absorption of tetraphenylporphyrin （TPP）, copper tetraphenyl- porphyrin （CuTPP）, zinc tetraphenylporphyrin （ZnTPP） and nickel tetraphenylporphyrin （NiTPP） in chloroform and pyridine at 532 nm is studied by using open aperture Z-scan. A theoretical analysis has been carried out to simulate ground state absorption cross-section, riplet state absorption cross-section and intersystem crossing time of the four samples by using five-level model. The change of solvent from chloroform to pyridine lead to a red shift of the absorption spectra of tetraphenyl metalloporphyrin, which affect their nonlinear absorption parameters. Generally, solvents have a remarkable influence on nonlinear absorption of tetraphenylporphyrin and tetraphenyl metalloporphyrin.