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The chemical oxidation of alternating branched polyarylamines leads to the formation of radical cations, the presence of which was manifested by the appearance of new bands in the UV-visible-near infrared spectra. Spins of radical cations can be magnetically coupled. The nutation pulsed-EPR technique was used to determine the multiplicity of spin systems for different oxidant:polymer unit ratios. It was found that spins of polymers oxidized to a radical cation in each conjugated amine segment interact magnetically to form dominant quartet state (S = 3/2). Magnetization measurements confirmed the ferromagnetic interaction of spins, returning an exchange integral J = +0.75 meV. [ABSTRACT FROM AUTHOR]

Triarylamines oxidized to radical cations can be used as stable spins sources for the design of high-spin compounds. Here, we present the synthesis of the polyarylamine-containing hexaazacyclophanes linked via meta-terphenyl bridges. Spins, created after oxidation of the polymer, can be coupled magnetically in cyclophane moieties via meta-phenyl and along the polymer chain via meta-terphenyl units. The formation of a quintet spin state was evidenced by pulsed-EPR nutation spectroscopy. Two exchange coupling constants via both couplers were determined experimentally and corresponded to J/k = 89 K in the cyclophane moiety and j/k = 17 K via meta-terphenyl. Most importantly, in this polymer, four spins can be ferromagnetically ordered via both couplers, which leads to the high spin state. [ABSTRACT FROM AUTHOR]

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]