Exchange interactions in R2Fe17-xGax (R = Y, Sm, Gd, Tb, Ho and Tm) compounds

摘要

We calculated the molecular field coefficients, n(FeFe) and n(RFe) (R = Sm, Gd, Tb, Ho and Tin), for R2Fe17-xGax and the values of nFeFe and n(SmFe) for R2Fe17-xTx (T = Al and Si) using the experimental values of the Curie temperature. The values of nFeFe increase in spite of the decrease of mu F-e for 0 <= x <= 5. The values of n(SmFe) have large values when the magnetic anisotropy is axial. For 6 <= x <= 8, the values of n(FeFe), n(HoFe) and n(TmFe) increase largely, which is related to the change of the easy magnetization direction. For Y2Fe17-xTx (T = Ga and Al), the values of n(FeFe) have a maximum value with increasing those of mu(Fe). With increasing V-1, the values of n(FeFe) have a maximum value around the same value of V-1 for Y2Fe17-xTx (T= Ga and Al). For Y2Fe17-xSix, the values of n(FeFe) increase with increasing V-1. (c) 2005 Elsevier Inc. All rights reserved.