Nd_2Fe_(14)B的价电子结构分析和磁性计算  

Analysis of valence electron structures and calculation of magnetic properties of Nd_2Fe_(14)B

作　　者：吴文霞[1] 郭永权[1] 李安华[1] 李卫[1] 

机构地区：[1]钢铁研究总院功能材料研究所,北京100081

出　　处：《物理学报》2008年第4期2486-2492,共7页Acta Physica Sinica

基　　金：国家高技术研究发展计划(批准号:2007AA03Z458);北京市科技研究计划重大项目(批准号:D0406002000091)资助的课题~~

摘　　要：应用固体与分子经验电子理论计算了Nd2Fe14B的价电子结构、磁矩和居里温度,计算结果与实验值相符.计算表明:该合金的磁性与3d磁电子数成正比.从Fe(c)晶位到Fe(k2)晶位磁矩增加,其机理源于价电子、哑对电子和3d磁电子之间的转化,有78%的哑对电子和18%的3d共价电子转化成了磁电子.居里温度和磁矩与Fe原子配位数成正比,与加权等同键数Iσ成反比,Nd原子和B原子通过调节原子间键距影响Nd2Fe14B合金的居里温度.The valence electron structure and magnetic properties of Nd2 Fe14 B intermetallics have been investigated using empirical electronic theory of solids and molecules. The calculations fit the experimental data well. It reveals that the magnetic properties of Nd2Fe14B are proportion to the 3d electrons of Fe atoms. The moments increase from the Fe at 4c site to the Fe at 16k2 site, which is due to the changes between the valence electrons, dumb pair electrons and 3d magnetic electrons. According to the calculation, 78% of dumb pair electrons and 18% of valence electrons in d orbit change to magnetic electrons, this causes the increase of moments from the Fe at 4c site to the Fe at 16k2 site. Both Curie temperature and moments are proportion to the coordination numbers of the Fe atom, however, the Curie temperature decrease with the weighted equal bond numbers F. The effect on Curie temperature of non-magnetic elements Nd and B is derived from the change of the Fe-B and Fe-Nd bond distances.

关 键 词：ND2FE14B 价电子结构 居里温度 

分 类 号：O482[理学—固体物理] O561[理学—物理]