Direct observation of the spin‐reorientation transition at Yb sites in YbFeO3

We report a direct observation of a 90° reorientation of Yb spins in YbFeO3 by Mossbauer spectroscopy of single crystals. Our spectra are consistent with a continuous rotation of the Yb spins in the region 6.6 K?T?7.8 K with second‐order phase transitions at the end points. Our results agree with qualitative predictions by Horner and Varma and by Yamaguchi, but the quantitative predictions of Yamaguchi are found not to apply to YbFeO3.