Electronic Properties of Some Complexes of Tetracyanoquinodimethan with Aromatic Diamines

Complexes of tetracyanoquinodimethan have been prepared with a number of aromatic diamines which are varied in their molecular shape and ionization potential. Infrared absorption spectra have revealed most of the complexes to be ionic in character. They showed a strong ESR absorption; in regard to its temperature dependence, however, three modes of variation were observed for these solid complexes. The complexes with N,N′-diphenyl-p-phenylenediamine and N,N′-di-β-naphthyl-p-phenylenediamine were considered to be of non-bonding type and showed no ESR absorption. However, no appreciable difference in semiconductive properties has been found between the ionic type and the non-bonding type complexes, except the complex of diaminodurene-TCNQ(1 : 2). The latter showed a high electrical conductivity and a paramagnetic behavior which was nearly independent of temperature.