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Updated: May 22, 2026

Detection of Nitric Oxide and Superoxide Radical Anion by Electron Paramagnetic Resonance Spectroscopy from Cells using Spin Traps
Published on: August 18, 2012
(Nitronyl nitroxide)-substituted trioxytriphenylamine radical cation tetrachlorogallate salt: a 2p-electron-based
Masato Kuratsu1, Shuichi Suzuki, Masatoshi Kozaki
1Department of Chemistry, Graduate School of Science, Osaka City University, Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan.
Abstract:
The synthesis and the solid state magnetic properties of (nitronyl nitroxide)-substituted trioxytriphenylamine radical cation tetrachlorogallate, NNTOT(+)⋅GaCl(4)(-), are reported. In the temperature region between 300 and 3 K, the magnetic behavior is characterized by the strong intramolecular ferromagnetic interaction (J/k(B)=+400 K) between the radical (NN) and the radical cation (TOT(+)) and the weak intermolecular antiferromagnetic interaction (J/k(B)=-1.9 K) between NNTOT(+) ions. Below 3 K, a 3D-type long-range magnetic ordering into a weak ferromagnet was observed (T(N)=2.65 K). The magnetic entropy (S(mag)=8.97 J K(-1) mol(-1)) obtained by the heat capacity measurement is in good agreement with the theoretical value of R ln3=9.13 J K(-1) mol(-1) based on the S=1 state.
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