THE ENERGETICS OF FORMATION OF DONOR-ACCEPTOR COMPLEXES BETWEEN AROMATIC DIAMINES AND HALOGENATED QUINONES

Author Institution: Chemistry Division, The Franklin Institute LaboratoriesThe ultraviolet, visible and infrared absorption spectra have been measured in the solid state for chloranil complexes with diaminodurene, p-phenylenediamine, and 1.6-diaminopyrene. The spectra show features indicative of radical ions in the crystals. The diaminodurene-chloranil visible spectrum indicates that the Wurster ion of the amine is present in its dimeric (diamagnetic) form. The ionization potentials of these amines have been measured also in the solid state, all having values from 5.2 to 5.5 ev. The usual relation between the charge-transfer band energy and the ionization potential of the donor cannot therefore be extended to donors of ionization potentials lower than about 5.5 ev because of the I-electron redox reaction which changes the nature of the donor-acceptor interaction