Electrical conduction in the phthalocyanines. I. Optical properties

Abstract

The polarized crystal and vapour spectra of metal-free, nickel, copper, zinc, chromium, cobalt, and iron phthalocyanines are reported and the results compared with published data. Comparison between these optical data and activation energies for dark conduction raises doubts as to the ability of the "singlet" or "triplet" theories to explain satisfactorily electrical conduction in organic semiconductors.