Influence of interchain interactions on the magic angle EPR linewidth of(CH3)4NMnCl3(TMMC) doped with Cu

Abstract

Electron paramagnetic resonance measurements at room temperature have been performed on the linear chain magnet ${(\mathrm{C}{\mathrm{H}}_{3})}_{4}$NMn${\mathrm{Cl}}_{3}$ (TMMC) doped with Cu. At higher frequency the magic angle linewidth shows a significant deviation from the expected ${\ensuremath{\omega}}^{\ensuremath{-}\frac{1}{2}}$ frequency dependence. The deviation can be explained by dipolar interchain interactions. There is evidence for interchain diffusion, which can be quantitatively explained by the isotropic part of the dipolar interaction. The intrachain diffusion is strongly influenced by the impurity concentration, whereas the interchain diffusion is hardly affected.