MOSSBAUER STUDY OF FERROUS ION IN SOME ANHYDROUS DIHALIDES OF IRON-GROUP ELEMENTS

The Mössbauer measurements on the ferrous ion in FeBr2, CoCl2 and NiCl2 are presented. Various interaction parameters are estimated from the observed spectra. The effect of anion change on the ferrous ion is discussed, comparing the results on FeBr2 with those on FeCl2 and FeI2 reported previously. The spectra observed below the Néel temperature show that the ferrous spin in CoCl2 is forced to lie in the c plane, whereas that in NiCl2 orients along the c axis which is the direction preferred by the ferrous spin. These can be interpreted in terms of the difference in anisotropy energy of the host spins. © 1969, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.