EPR experiments in the one-dimensional salt (${\mathrm{C}{\mathrm{H}}_3)}_4$NMn${\mathrm{Cl}}_3$ (TMMC) at temperatures between 4.2 and 70 K

EPR experiments at low temperatures have been performed in the one-dimensional antiferromagnet ${\left(\mathrm{C}{\mathrm{H}}_3\right)}_4$NMn${\mathrm{Cl}}_3$. Two resonances have been observed: one due to the manganese ions in the linear chains and a second of unknown origin. The temperature dependences of the positions and linewidths of the resonance lines have been analyzed in terms of the available theory.