First-Principles Study of Structural and Magnetic Properties of R(Fe,Ti)12 and R(Fe,Ti)12N(R=Nd,Sm, Y)

We study the effects of interstitial nitrogenation to magnetic properties of ThMn12-type compounds RFe11Ti and RFe12 with R = Nd, Sm, Y by using first-principles technique. The magnetocrystalline anisotropy is estimated from the crystalline-electric-field parameter A02 at the rare-earth site. The change in ⟨r2⟩A02 by nitrogenation is nearly independent of Ti substitution and has a little dependence on the rare-earth element. NdFe12N has considerably larger magnetization and slightly less (but strong enough) uniaxial magnetocrystalline anisotropy compared with NdFe11TiN, thereby NdFe12N is expected to be a quite high performance permanent magnet material.

科研費新学術領域「コンピューティクスによる物質デザイン」、次世代スパコン戦略プログラム、CMSI