Electrochemistry and Spectroelectrochemistry of Polynuclear Zinc Phthalocyanines: Formation of Mixed Valence Cation Radical Species

The electrochemistry and spectroelectrochemistry of mononuclear, binuclear and tetranuclear zinc neopentoxy-substituted phthalocyanines are presented. The binuclear and tetranuclear species show two oxidation waves to the radical cation indicating the existence of stable mixed-valence, half-oxidized species. The electronic spectra of the half− and fully-oxidized species are presented and discussed. Nernstian analysis shows that pairs of phthalocyanine rings are oxidized simultaneously in the tetranuclear species, via a one-electron oxidation pathway.