Pseudo-para-dinitro[2.2]paracyclophane Radical Anion, a Mixed-Valence System Poised on the Class II/Class III Borderline

Abstract

Analysis of optical spectra of a pseudo-para-dinitro[2.2]paracyclophane radical anion using Marcus-Hush theory reveals that its off diagonal coupling element, H(ab), is large enough, relative to its reorganization energy, to change it from a localized class II compound to a delocalized class III compound by changing solvents. The optical spectra, along with frontier orbital analysis, show that the assumption that E(op) = 2H(ab) for class III compounds is not true in this case.