FORMATION OF PHOTOCHEMICAL PI-CATION RADICALS .1. MU-OXO-IRON(III) TETRAPHENYLPORPHYRIN

We have monitored the spectra and kinetics of -oxo iron (III) tetraphenyl porphyrin. The spectral changes between 460 nm and 770 nm were observed after excitation with 25 ps fwhm, 355 nm pulse. Kinetic studies from 100 ps to 4 ns suggest that after the immediate formation of the excited states a transient species is formed which we assign to the -caion radical-ferrous porphyrin pair. This pair decays with a time constant of 600 ps 100 ps leaving a small amount of disproportionation reaction photoproducts. The spectra and kinetics of the transients, were not altered by concentration (0.15 OD 1.0 OD at 571 nm), solvent or addition of oxygen. 1989, Springer. All rights reserved.

FORMATION OF PHOTOCHEMICAL PI-CATION RADICALS .1. MU-OXO-IRON(III) TETRAPHENYLPORPHYRIN Academic Article