The effect of weak exchange interaction on electron paramagnetic resonance in dichloro bis-o-phenylene bis-dimethyl arsino nickelate(III) chloride

The observation of a single exchange-narrowed E.P.R. line in [NiCl₂-(diars)₂]Cl, a monoclinic crystal with two magnetically inequivalent sites, is shown to be due to g-averaging and hence the concentration dependence of the g-tensor is explained. The lineshape analysis and the angular dependent linewidth data are used to evaluate various Fourier components of the spin-correlation function using Kubo-Tomita theory. The total linewidth is partitioned into secular and non-secular contributions of the broadening mechanisms—dipolar and hyperfine interactions. The angular dependence of the " 10/3 effect " observed in X- and 0-bands could not be predicted by either the Blume-Hubbard or the Anderson-Weiss model. In the 7 regime [ℋz≈12 500 G or 3200 G> ℋex≈ 700 G> ℋdipolar, ℋhyperfine f«70 G] of [NiCl₂(diars)₂]Cl there is paucity of both experimental and theoretical studies. Taylor & Francis Group, LLC.