Spin reorientation in Tb/sub 1-x/Y/sub x/Fe/sub 11/Ti compounds

The Tb/sub 1-x/Y/sub x/Fe/sub 11/Ti (x=0, 0.2, 0.4, 0.6 and 0.8) compounds have been studied in magnetization and AC-susceptibility measurements as a function of temperature. The results show that the Tb/sub 1-x/Y/sub x/Fe/sub 11/Ti compounds with x=0, 0.2 and 0.4 undergo a spin reorientation of the axis-to-plane type (referred to decreasing temperature), while the samples with x=0.6 and 0.8 remain easy-axis compounds down to the lowest temperature measured (4.2 K). The spin-reorientation temperature, T/sub sr/, is found to decrease with increasing Y content. The observed temperature dependence of the magnetic structure of this series of compounds has been analyzed on the basis of a crystal-field model with the following set of crystal-field parameters: B/sub 2//sup 0/=0.45 K, B/sub 4//sup 0/=-1.8/spl times/10/sup -4/ K and B/sub 6//sup 0/=0 K.<
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