MAGNETIZATION OF A DY(FE11TI) SINGLE-CRYSTAL

Magnetization curves have been measured in the temperature range from 4.2 to 300 K along the [100], [110], and [001] directions of a Dy(Fe11Ti) single crystal in fields up to 7 T. The magnetic moment is along [100] below 58 K and parallel to the c axis above 200 K. Between the two spin-reorientation transitions (first order at 58 K, second order at 200 K) there is a canted spin structure where the net magnetization lies in a (010) plane and is inclined at an angle to the c axis. Three first-order magnetization processes are observed as a function of applied field below 150 K. All the data are used to derive a set of five crystal-field coefficients at the single rare-earth site of the ThMn12 structure: A20=-32.3 Ka0-2, A40=-12.4 Ka0-4, A44=118 Ka0-4, A60=2.56 Ka0-6, A64=0.64 Ka0-6. Spin reorientation observed in the other members of the R(Fe11Ti) (R==rare earth) series, except those in Tb(Fe11Ti), are explained by the same crystal-field coefficients. © 1990 The American Physical Society.