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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]

Thisreport describes the study of a dimer d2+and a linear trimer t3+of amminium radical cations coupled by 3,4′-biphenylspin coupling units. The synthesis of the parent diamine and triamineand their optical and electrochemical properties obtained by UV–visibleand cyclic voltammetry are presented. The chemical doping of the parentdiamine dand triamine twas performed quantitativelyto obtain samples containing the corresponding dimer d2+and trimer t3+in almost pure high-spin states as evidenced by pulsed EPRnutation spectroscopy. The Jcoupling constants ofthe corresponding S= 1 and S=3/2 spin states were measured (J/k= 135 K) and compared quantitatively to DFT calculations. [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]