Electron Paramagnetic Resonance in the Quasi-One-Dimensional Jahn-Teller-Crystals. I. CsCuCl3

Abstract

We report the results of the EPR measurements performed on the single crystals of CsCuCl 3 in the temperature range 120 K to 560 K at X- and K-band frequencies. Discontinuous changes in the linewidth and the shift of resonance field are observed at the structural phase transition point of 420 K. The EPR properties, i.e. the magnitude of the linewidth, its anisotropy, the anisotropy of resonance field, etc, observed in both the high- and low-temperature phases can be interpreted in terms of the exchange modulation of the Dzyaloshinsky-Moriya antisymmetric interaction. This fact indicates that the CuCl 6 octahedra in CsCuCl 3 are already distorted above the transition point and the relaxation time of the distortion is much longer than 10 -12 sec.