EPR lineshape study of the incommensurate phase in γ-irradiated K2SeO4

The temperature dependence of the SeO4-4 EPR frequencies and the asymmetric broadening of the EPR lines in the incommensurate phase of K2SeO4 can be explained by an incommensurate spatial modulation of the g tensors which corresponds to the “broad” phase soliton limit. A comparison between the experimental and calculated lineshape shows a ≈1% volume fraction of commensurate regions in the middle of the incommensurate phase at 110 K.