“Molecular Metals” Based on Copper(II) 2,9,16,23-tetrahalo Substituted Phthalocyanine Derivatives

Abstract

Pure copper(II) 2,9,16,23-symmetrically tetrahalo substituted phthalocyanine complexes, CuPTX (where X = F, CI, Br and I) were synthesized. Elemental analyses, electronic, IR, magnetic susceptibility measurements, ESR, X-ray diffraction and TGA studies were carried out on the above complexes both before and after iodine doping, to characterize and investigate the effect of substituents as well as the iodine doping on the electrical properties of the copper phthalocyanine complexes. Variations in the electrical conductivity of the complexes depend on the nature of the substituents and were found to show ∼10⁵ times improved electrical conductivity in comparison to the parent phthalocyanine. It is interesting to note that substitution and iodine doping showed remarkably increased electrical conductivity, nearly 10¹² times the electrical conductivity of copper phthalocyanine. This may be due to a decrease in the metal-metal bond distance, increase in the approach of an ideal eclipsed system or due to the combined effects of both.