SOLID-STATE C-13 NMR IN CONDUCTING POLYMERS

We present a **1**3C NMR study of polythiophene, polypyrrole and polyaniline. The results have been obtained by cross-polarization with proton decoupling and magic angle sample spinning techniques. Using selective polarization, we have been able to separate the lines of inequivalent carbons and to estimate their chemical shift. From the results, we determine the structure of polyaniline and we discuss the oxidation scheme of the polymeric chain in polythiophene and polypyrrole. We also give an estimate of the **1**3C paramagnetic shift.