Si原子择优占位对R_2Co_(17)化合物中Co次晶格磁晶各向异性的影响

INFLUENCE OF PREFERRED OCCUPATION OF Si ATOMS ON MAGNETOCRYSTALLINE ANISOTROPY OF Co SUB-LATTICE IN R_2Co_(17) COMPOUNDS

对R2Co17-xSix（R＝Ce，Gd和Y）化合物的X射线衍射和磁性测量研究结果表明，Si原子的加入使R2Co17化合物的室温磁晶各向异性由易面转变为易轴，各向异性常数随Si原子浓度的增加而出现极大值、重点讨论了Si原子在Co次晶格四个不同晶位择优占位与Co次晶格磁晶各向异性演化的关系。

Preferred occupation of Si atoms and magnetic properties of R2Co17-xSix compounds (R=Ce, Gd 和 Y) were studied by means of X-ray diffraction and magnetic measurements. The preferential site substitution of Si atoms for Co leads to a change of the magnetocrystalline anisotropy from easy-plane to easytals at room temperature, and also results in a makimum in magnetocrystalline anisotropy constant with increasing Si concentration. A special attelltion has been paid to the relationship between the preferred site occupation of Si atoms over the four available crystallographic sites on the Co-sublattice and the evolution of magnetocrystalline anisotropy of the Co-sublattice.The 18h site plays a profound role in negative contribution to the Co-sublattice anisotropy in R2Co17 compounds.