The 20th ESICMM Seminar

Recently, we have performed very detailed calculations and analyses on magnetic moment and magnetic anisotropy of NdFe₁₁TiX (X=B, C, N, O, F) [1] with particular emphasis on the roles of typical elements.  Magnetic moment of NdFe₁₁TiX is strongly affected by magneto-volume effect which is insensitive to the kind of X and the chemical effect which is sensitive to X.  The “cobaltization” concept [2] of Kanamori is an important factor in the chemical effect and yet it is not sufficient to explain the trend of the magnetic moment variation among X.  We pointed out the important role of anti-bonding states formed by the X-Fe hybridization where not only Fe-3d states but also Fe-4sp states play important roles.  We also pointed out the importance of the local symmetry of X.  In the last respect, NdFe₁₁TiN and NdFe₁₂N are special among the rare-earth magnets.

[1] Y. Harashima et al.: submitted to Phys. Rev. B; arXiv:1507.03777v1.

[2] J. Kanamori, Prog. Theor. Phys. Suppl. 101, 1 (1990).