Magnets configurations/arrangements

Figure 12.5 The relationship between the ordered arrays of magnetic dipoles arranged on a square lattice (a) ferromagnetic configuration, (h) canted antiferromagnetic configuration and (c) antiferromagnetic configuration...

In keeping with tlie arrangements ot Mayer s magnets, Thoinrou s configuration shifted to a second ring at six electrons, wailed until 10 electrons lo add a first electron to the sec-... 

For the octahedral case in Fig. 5-1, we include mention of the number of unpaired electrons associated with each arrangement. For real molecules we could use this to determine which configuration is lowest in energy - whether oct or P were the greater - if only we had some experimental method of measuring the number of unpaired electrons. There is such a method and it depends upon the interaction of these molecules with a magnetic field. 

The first condition concerns the electronic configuration of the cations, the second one the arrangement of ions in the lattice, the crystal structure. Depending on the combination of those different factors, superexchange may occur in 3, 2 or 1 dimensions or fail to appear. Examples of all these four cases wiU be discussed in the following in context with the magnetic structures of fluorides. 

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