EPR OBSERVATIONS OF POSITIONAL DISORDER OF THE [(CH3)(3)NH](+) IONS IN [(CH3)(3)NH]CDCL3

Two chemically inequivalent [N(CH3)(3)](+) radical species produced vi a gamma-irradiation were detected by EPR in the low-temperature, ortho rhombic 1 x root 3 phase of [(CH3)(3)NH]CdCl3. This indicates a twofol d, static disorder of the [(CH3)(3)NH](+) (TrM) ions. One of the radic al species could be identified as originating from the ''normal'' TrM ions and the other from the ''disordered'' TrM ions. The EPR result al so indicates that the population ratio of the ''disordered'' TrM ions relative to the ''normal'' TrM ions is temperature dependent; this rat io decreases with decreasing temperatures.