Synthesis of Axially Substituted Tetrapyrazinoporphyrazinato Metal Complexes for Optical Limiting and Study of Their Photophysical Properties

摘要

The synthesis,characterization,and various photophysical properties of axially substituted tetrapyrazinotet-raazaporphyrinatotitanium(IV) oxide (Pyz_4TAPTiO) (1),tetrapyrazinotetraazaporphyrinatovanadium(IV) oxide (Pyz_4TAPVO) (2),tetrapyrazinotetraazaporphyrinatozirconium(IV) dihydroxide [Pyz_4TAPZr(OH)_2] (3) are reported.Nonlinear optical (NLO) properties of Pyz_4TAPs 1-3 have been evaluated at 532 nm with nanosecond pulses for optical limiting (OL).It is found that the introduction of nitrogen atoms in the condensed rings of the tetrapyrrolic macrocycles together with the presence of axial substituents lead to an improvement of the excited-state absorption properties in comparison to phthalocyanines (P_(CS)).In the linear optical regime Pyz_4-TAPs 1-3 display a blue shift (about 50-60 nm) of the main UV-vis absorption bands with respect to P_(CS) and exhibit orange-red fluorescence,which can be observed with the eye in the case of 1.Frontier electronic orbitals of a Pyz_4TAP could be depicted from available experimental data and the results of density functional theory (DFT) calculations.In the solid state,Pyz_4TAPTiO (1) displays photoconducting properties.