Magnetic anisotropy of R2Fe14B (R=Nd, Gd, Y): Density functional calculation by using the linear combination of pseudo-atomic-orbital method

The magnetocrystalline anisotropy energy (MAE) of rare-earth transition-metal intermetallics R2Fe14B (R = Nd, Gd, Y) was calculated by using the linear combination of pseudo-atomic-orbital method. Electronic structures were calculated by using relativistic density functional theory with Hubbard-type on-site Coulomb potential U for f electrons in the R sites. The calculated magnetic moments of Y2Fe14B and Gd2Fe14B are in agreement with the experimentally measured saturation moments of these compounds. The calculated MAEs of Y2Fe14B and Gd2Fe14B are also in agreement with the value measured at low temperature. Moreover, it was found that the shape of the charge density at the Nd sites is aspherical, which causes larger MAE of Nd2Fe14B than that of Gd2Fe14B. However, the orbital moment of the 4f electrons at the Nd sites and the MAE of Nd2Fe14B were underestimated within the scope of a relativistic local-density approximation plus U with spherical average potential.