Mössbauer, EPR and susceptibility studies of highly conducting polypyrrole doped with iron chloride

The results of Mossbauer, EPR and static magnetic susceptibility measurements on polypyrrole doped with FeCl3 are presented. They indicate that iron chloride tetrahedra are interacting with the polymer matrix by hydrogen bonding. This interaction increases with dehydration of the samples. The susceptibility showed a maximum near 5 K, which is an indication for antiferromagnetic interaction, probably between paramagnetic iron and polarons.