Study of magnetic relaxation in the perovskite SrLaFeSnO6 by Mössbauer spectroscopy
The temperature dependence of the 57Fe and 119Sn Mössbauer spectra of SrLaFeSnO6 has revealed the existence of unusual magnetic relaxation behaviour. The transferred hyperfine interactions in the Sn resonance at 4.2 K establish that the Fe and Sn cations are disordered. An explanation is developed in terms of the formation of magnetic clusters below ca. 220 K which increase in size with decreasing temperature until a long-range ordered G-type antiferromagnetic structure is achieved below ca. 38 K. This behaviour is intermediate between a true antiferromagnet and a spin-glass. A reinterpretation of the related SrFe1 –xSnxO3 –y system is given which suggests that compositions in the region of Sr2FeSnO5.71 may also exhibit spin-glass behaviour.