The results of electron paramagnetic resonance (EPR) experiments are reported for chemically synthesized polypyrroles soluble in organic solvents, which have different doping levels. Pauli susceptibility (Formula presented) and the density of states (Formula presented) are obtained from the temperature dependence of magnetic susceptibility. The (Formula presented) and the (Formula presented) increase as the doping level increases, which indicates that the system becomes more highly conducting. The electron spin-lattice relaxation time (Formula presented) is measured by using saturation methods. The (Formula presented) decreases with increasing doping level at room temperature. This implies that the spin-lattice interaction easily occurs in the sample with the high concentration of dopants. The EPR linewidth (Formula presented) linearly increases as temperature increases from 100 K to room temperature. We use a Korringa relaxation rate to account for the temperature dependence of the (Formula presented).
|Number of pages
|Physical Review B - Condensed Matter and Materials Physics
|Published - 1999
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ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics