Ferrimagnetic crystal

These data together with the refractive indices provide one of the most effective structural characterizations of a solid. Optical methods are particularly sensitive in detecting pseudosymmetric forms of a higher symmetry phase and, therefore, for detecting phase changes with temperature in ferroelectric, antiferroelectric, and transparent ferrimagnetic crystals. 

Figure 5.31 Magnetic ordering in (a) ferro, (b) antiferro and (c) ferrimagnetic crystals.

There is technical interest in ferrimagnetics. The majority of than are antiferromagnetics, the structure of which includes two (or more) ions whose magnetic moments differ, and therefore sublattices do not completely compensate each otha in the crystal. The macroscopic magnetic moment arises. In many respects, a ferrimagnetic crystal behaves as a ferromagnetic one. The domain structure and, consequently, a hysteresis loop, also exhibit. 

In this paper only the aspects of structural chemistry of the more common structure types adapted by fluorine compounds will be considered. There wiU also be a brief account of the cooperative phenomena of antiferro- and ferrimagnetism, that are strongly dependent on crystal structures. For all information on preparation and chemical properties of transition metal fluorocomplexes, especicilly interesting for the high valency states, the reader is referred to the excellent reviews given by Sharpe (278) and by Peacock (255). 

Birss, R.R., Martin, D.J. (1975) The magnetization process in hexagonal ferromagnetic and ferrimagnetic single crystals, J.Phys.C Solid State Phys. 8 189-210. 

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