High field electrical conduction in some organic charge-transfer complexes

Abstract

The semiconductivity of perylene–chloranil and perylene–2,3-dichloro-5,6-dicyano-p-benzoquinone complexes has been investigated in the temperature range 150 to 345 K with applied electric fields up to 10⁷ V m^–1. Results obtained from the analysis of generalized current against temperature plots suggest that the high field conduction mechanism is a bulk process between Poole–Frenkel type centres. Values have been derived or estimated for such electronic parameters as the charge carrier concentration and mobility, and the energies and concentrations of the dominant donor and trapping sites. An extrinsic conduction mechanism involving the M⁺A^– complex, where M is an impurity metal such as Na, is developed to describe the semiconductivity of these and some other charge-transfer complexes whose electrical characteristics have been reported in the literature.