Magnetic phase transition, aggregate formation, and electrical conductivity in FeC13-doped polyacetylene
نویسندگان
چکیده
Both Fe3 + and Fe2 + ions occur in FeCl3-doped polyacetylene. At low dopant levels ( < 0.01 mole frac tion) both Fe2 + and Fe3 + io'ns are paramagnetic down to 4.2 K. At dopant levels > 0.01 mole fraction, there is evidence from Mossbauer spectroscopy that Fe2+ ions associate into aggregates which are magneti cally ordered below 25 K. Aggregate formation appears to correlate with high electrical conductivity.
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