CONDUCTIVITY IN DIALKYLSULFIDE-IODINE MIXTURES

Mixtures of iodine and dialkylsulphides are liquids with a significant electrical conductivity, especially in the range of high iodine concentrations. A linear relationship exists between the logarithm of the conductivity and the weight percentage of iodine in the mixtures over more than four magnitudes of conductivity and nearly the whole concentration range. After both compounds are mixed a chemical reaction takes place. This reaction does not change the organic sulphide, but yields to a charge transfer interaction of the iodine as acceptor and the sulphide as donor and to the formation of polyiodides by charge separation. These results were obtained by Raman, 1HNMR and ir-spectroscopy. The formation of radicals can be excluded, as shown by magnetic measurements. It is assumed that the conductivity process is based on a mechanism of the Grotthus-type, represented formally by a series of simple ion transfer steps in the polyiodide structure. © 1990.