Electrochemical and charge transfer studies were used to determine the electron aff• (EA) of fifteen electron acceptor compounds. The behavior of these materials as electron transport species was evaluated by the photoinduced discharge curve (PIDC) method. The relation between the PIDC results and such electrochemical information as reversibility of the charge transfer step and polarization effects is discussed and it is shown that irreversible electrochemistry correlates with deep trapping phenomena. In addition, the results are discussed in terms of a simple model which relates electron affinity to charge carrier mobility.

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NMR relaxationtime studies of poly(Nvinyl carbazole) and sorbedO2 effectsThe dielectric relaxation spectrum of poly(N-vinylcarbazole) (PVK) and poly(3-chloro-N-vinylcarbazole) (CLPVK) have been investigated in the temperature range -180-+ 240 DC. Four relaxations are observed in PVK. The a relaxation (225°C) is associated with the glass transition of the polymer. On the basis of oxygen-sorption experiments, the y relaxation (--60°C) has been associated with a rotationallibration of the pendant carbazole group. It is also speculated on the basis of this work that an off-axis dipole is induced in the carbazole moiety by the sorbed O 2 producing the dielectrically active motion about the symmetry axis of the carbazole moiety. The 13 (-80°C) and the Il (--160°C) relaxations are assigned as carbazole wagging motions and localized backbone motions, respectively. These assignments are based on comparative work in the literature.PACS numbers: 77.40.

The γ and δ relaxations of polystyrene (PS) are rendered more active dielectrically by sorbed oxygen. This effect, coupled with comparative work on molecularly similar systems has led to the assignment of the γ relaxation to a rotational libration of the phenyl ring in PS. Specific interactions of the pendant phenyl ring with molecular oxygen to induce off‐axis dipole moments in the phenyl moiety is proposed. It is concluded that this interaction is strong enough to influence the dielectric relaxation strength of other relaxations in PS. It is further concluded that because of the interactions occuring in aromatic polymers containing sorbed oxygen, care must be taken to exclude oxygen or to vary its content, in order that intrinsic motions in the polymer system can be studied.