Tuning of FerromagneticSpin Interactions in PolymericAromatic Amines via Modification of Their π-ConjugatedSystem.

Polyarylamine containing meta–para–para-aniline units in the main chain and meta–para-aniline units in the pendant chains was synthesized. The polymercan be oxidized to radical cations in chemical or electrochemicalways. The presence of meta-phenylenes in the polymerchemical structure allows for the ferromagnetic coupling of electronicspins, which leads to the formation of high spin states. Detailedpulsed-EPR study indicates that the S= 2 spin statewas reached for the best oxidation level. Quantitative magnetizationmeasurements reveal that the doped polymer contains mainly S= 2 spin states and a fraction of S=3/2 spin states. The efficiency of the oxidation was determined tobe 74%. To the best of our knowledge, this polymer is the first exampleof a linear doped polyarylamine combining such high spin states withhigh doping efficiency. [ABSTRACT FROM AUTHOR]