ESR Studies of Porphyrin π-Cations: The 2A1u and 2A2u States
Fajer, J., Borg, D.C., Forman, A., Felton, R.H., Vegh, L., and David Dolphin
Ann. N.Y. Acad. Sci.
The existence of 2 distinct ground states with remarkably different properties is suggested for porphyrin π-cations on the basis of literature evidence for oxidation of the π system and the correlation of ESR data and MO calculations: these ground states are 2 A2u , typified by the Mg- and Zn-meso-tetraphenylporphine radical cations, and 2A1u , typified by Mg and Zn octaethylporphine radical cations. The ESR spectra were obtained after 1-electron oxidations of the parent compounds and their selectively deuterated analogs.