Magnetic Properties of N-Nonylphenothiazine Radical Cations Depending on Counter Anions

Abstract

Magnetic properties of N-nonylphenothiazine radical cations were found to vary depending on their counter ions. The radical cations in NTf2– (bis(N-trifluoromethanesulfonyl)imide ion), OTf– (trifluoromethanesulfonate), and BF4– salts formed π-dimer with strong antiferromagnetic interactions. The SbF6– salt exhibited paramagnetic properties with quite weak antiferromagnetic interaction. Interestingly, the NTf2– salt transformed to the paramagnetic liquid state upon heating to 78 oC.