Preferred magnetization direction

Second-order Stevens factor for different R elements and preferred magnetization direction observed in various R2Fe14B and R2Co17 compounds. (After Buschow et al. 

In two series of compounds both related to permanent magnet materials the easy magnetization directions and the values of a, of the various R components may be compared with each other. It may be seen from table 10 that there is a perfect correspondence between the sign of a, and the occurrence of a given preferred magnetization direction within each series of compounds (Sinnema et al. 1984, Callen 1982). In the series RCo5, the situation is almost the same as in the series R2Co17. 

Symmetry (referred to Fig. 3) Lower eigenvalue of the magnetic dipolar tensor Preferred spin direction angle with axes ... 

Figure 8 The result of applying a magnetic field normal to the preferred spin direction for an antiferromagnet. The spins are misaligned by a small angle , giving rise to a small, net moment...

R2Fe14B is their magnetocrystalline anisotropy. It was shown by several authors that the Fe sublattice magnetization has its preferred direction parallel to the c-axis while the Co sublattice magnetization prefers a direction perpendicular to the c-axis... 

Note that with regard to anisotropy energy and exchange energy there is no preference for either of the magnetization directions of the two domains in zero applied field. 

In the presence of external magnetic fields both substances show a molecular alignment, with the long axes of the molecules preferring a direction... 

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