The Electrical Conduction of Iodine Complexes of Aromatic Diamines

The magnitudes and temperature dependence of the electrical resistivities of aromatic diamine - iodine complexes have been studied on four aromatic diamines; 1,5-naphthylenediamine (NDA), benzidine (BEN), o-tolidine (TOL) and p, p′-diaminodiphenylmethane (APM). As the donor is a non-conjugated molecule, the electrical conductivity of its iodine complex is inferior to that of the conjugated diamine. BEN and TOL, which are polyphenylenediamines, are better electron donors for iodine than NDA, a diaminopolyacene; the characteristics of the electron donor for iodine of NDA are as strong as those of p-PDA. The resistivity shows a minimum value at an iodine mole ratio above 1.0 in the cases of the conjugated aromatic diamine which involve two benzene rings. These iodine contents are higher than the corresponding value p-PDA-iodine, 0.8.