A theoretical study is made of low-temperature spin reorientation in ErFeO//3, with consistent inclusion of Er**3** plus ion states in the crystal and exchange fields. Analytical expressions are derived for the temperature dependence of the angle of rotation of the iron sublattices, the splitting of the ground doublet of the Kramers ion Er**3** plus , and the magnetization of the rare-earth subsystem in the spin reorientation process. From experimental results at very low temperatures (1. 2-1. 5 degree K), the whole temperature dependences of these quantities is reconstructed, and in particular the phase transition temperature 3. 95 degree K is obtained. The effect of an external field on the phase transition temperature is also examined. A comparison with experiment indicates that the model is an adequate one.
|Number of pages||6|
|Journal||Sov Phys Solid State|
|State||Published - 1978|