Correlation between π-orbital overlap and conductivity in bis-phthalocyaninato lanthanides

Conductivity measurements on praseodymim, neodymium, gadolinium, holmium, erbium, and lutetium phthalocyanine sandwich compounds of the general formula H[M(Pc) 2)] taken with both D.C. and A.C. techniques on pressed pellet samples show a direct correlation with the intraplanar separation between the phthalocyanine ligands. Conductivity measurements on the iodine-dcped bis-phthalocyaninato lanthanides, H(M(Pc)2I x], show an average increase of four orders of magnitude when measured with D.C. techniques, and two orders of magnitude when measured with A.C. techniques. The high-temperature conductivity behavior may be explained by using the mobility model. The low-temperature data show hopping conduction behavior