Gd_3Co_(29-x)Cr_x新相化合物的结构与磁性  

Structural and magnetic properties of Gd_3Co_(29-x)Cr_xcompounds

作　　者：王文全[1] 闫羽[1] 王向群[1] 王学凤[1] 苏峰[1] 金汉民[1] 

机构地区：[1]吉林大学物理学院

出　　处：《物理学报》2003年第3期647-651,共5页Acta Physica Sinica

摘　　要：制备出具有室温单轴磁晶各向异性的非间隙型Co基Gd3Co2 9-xCrx 化合物 (x =6 5和 7 0 ) ,x射线衍射和磁性测量表明所有单相化合物均属于单斜晶系 ,Nd3(Fe ,Ti) 2 9型结构和A 2 m空间群 .Gd3Co2 9-xCrx 化合物的居里温度在x=6 5时为 4 12K ,x =7 0时为 35 9K .Gd3Co2 9-xCrx 化合物在x =6 5时磁化强度随温度的变化曲线表明 ,在居里温度以下的某一温度处有一补偿点 ,在补偿点处求得晶格分子场系数nRT=3 3Tf.u . μB.The novel Co-based Gd3Co29-xCrx compounds with a Nd-3(Fe,Ti)(29)-type structure have.been synthesized successfully for x = 6.5 and 7.0. The crystal structure and magnetic properties of the Gd3Co29-xCrx compounds have been investigated by x-ray diffraction analysis and magnetic measurements. It has been found that Gd-3(Co, Cr)(29) with x = 6.5 and 7.0 are ferrimagnetic with the Curie temperature of 412 K for x = 6.5 and 359 K for x = 7.0. Temperature dependence of magnetization shows a compensation point of the magnetization at a certain temperature below Curie point. The intersublattice molecular field coefficient, n(RT), was derived to be 3.3 T f.u./mu(B) for Gd3Co22.5Cr6.5 on the basis of the magnetization curve at the compensation temperature. It is noteworthy that the Gd-3(Co,Cr)(29) compounds exhibit a favourable easy-axis anisotropy in the whole temperature range below the Curie temperature.

关 键 词：结构 磁性 Gd3Co29-xCrx化合物 x射线衍射 磁晶各向异性 稀土-铁基金属间化合物 永磁材料 

分 类 号：O482.5[理学—固体物理]