The structural and magnetic properties of R2F17-xSix compounds have been investigated by means of X-ray diffraction and magnetization measurements. Substitution of Si for Fe leads to a clear reduction of the unit-cell volume. With increasing Si content, a phase transition from the Th2Ni17- to the Th2Zn17-type of structure has been observed for R=Tb, while all compounds crystallize in the Th2Ni17-type of structure for R=Er. A clear decrease of the saturation moment and an increase of the Curie temperature have been found upon Si substitution. The exchange-interaction constant J(TbFe) between the Tb and the Fe moments has been obtained from a mean-field analysis of the Curie temperature T-c. The X-ray diffraction patterns of magnetically-aligned powder samples show that the easy magnetization direction is in the plane for all compounds investigated. (C) 1999 Elsevier Science S.A, All rights reserved.
参考文献
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%