Aromatic complex with iodine, conductivities

The highest conductivities thus far observed in organic molecules are found among the donor-acceptor complexes. The activation energies for conduction are small, on the order of 0.1 eV ( 2 kcal) or less. Examples are the complexes of aromatic hydrocarbons with iodine and complexes of amines with chloranil or related quinones. The best conductors have a high free-radical content and are usually not of simple stoichiometry. The complex salts of TCNQ ° (I) are the best of the known organic conductors. The... 

Poly-/ -phenylene (10) doped with 0.005 mole I2 per C6H4 unit gave a spectrum showing a single iodine site, with <3 = 0.94 and e2q 21Qhrl = -2296 MHz23. These parameters are very like those for the -complexes with other aromatics discussed above (Tables 5 and 6) the iodine is therefore present in molecular form, weakly bound to the aromatic rings. This is consistent with the very low increase in conductivity and the ready loss of iodine under vacuum. 

The electrical conductivity of iodine and TCNQ complexes of a number of types of ionene polymers including those with aromatic rin g incorporated into the ionene backbone have been extensively studied. 

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