Chain lengths and electrical conductivity in polyacetylene

The high frequencies properties of (CH)$_x$ are fundamental in magnetism. Applications of (CH)$_x$ in junctions or electrode materials require the knowledge of the low frequencies properties. The depolarization thermocurrents allow the ultra low frequency range to be attained and the correspondence between depolarization thermocurrents and frequency dependence of conductivity in Durham (CH)$_x$ has been studied. The nature and distribution of the traps are welldefined in surface and bulk; the nature and distribution of the traps in the bulk are shown to be the same in Durham and in trans Shirakawa samples, the only difference being a higher traps density in Durham: consequently the effect of chain ends is pointed out