Slater-Bethe curve

Fig. 4.9. This plot, known as the Bethe-Slater curve, gives the correct sign for Fe, Ni and Co are ferromagnetic (parallel, > 0) Mn and Cr are antiferromagnetic (antiparallel, < 0). The shortcomings of this model have been discussed by Herring (1962) however, it remains as an instructive approximation.

Fig. 4.9. The Bethe-Slater curve, defining the sign of the exchange integral, for transition metals. (Adapted from Cullity, 1972.)...

Figure 12.8 The Bethe Slater curve for the magnitude of the exchange integral as a function of D/d, where D is the separation of the atoms in a crystal, and d is the diameter of the 3d orbital...

Bethe-Slater type curve in which the Curie temperature rather than the exchange energy is plotted against the ratio of atomic radius to the radius of the d-electron shell (f-electron shell in the case of Dy). Negative temperatures for Cr and Mn correspond to their Neel temperatures. (Data taken from Kittel, 7th edn., 19%). 

FIGURE 33.6 The Slater-Bethe curve showing the magnitude and sign of J as a function of D/d. 

The magnitude and the size of J depend on the interatomic separation, D, and the diameter, d, of the electron orbital under consideration as shown in Figure 33.6 (the Slater-Bethe curve) for the case of the 3d orbitals of Fe, Co, and Ni. 

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