LMTO法研究NdFe_(10)M_2的电子结构与磁性能

Studies of Electronic Structure and Magnetic Properties of NdFe_(10)M_2(M=Ti,V,Cr,Mn,Mo,W)Compounds by LMTO Method

采用能带论中线性Muffin－tin轨道方法，计算了NdFe(10)M2（M=Ti，V，Cr，Mn，Mo，W）及渗N和C原子后材料的电子结构，得到了相应的总体态密度（TDOS）和各晶位的局域态密度（DOS），并由净自旋数（电子数）得出了相应的磁矩及其变化，计算值与实验值相符合。在NdFe(10)M2中，N（或C）原子进入填隙位后，引发的两种不同的机制作用使材料磁性发生变化，8i和8f位由于体膨胀效应增强了Fe－Fe的交换作用，使8i和8f的磁矩增大，而8j位的Fe原子由于与填隙位的N（或C）的轨道杂化，而生成FeNx（或FeCx）化合物，因而使8j位的磁矩降低，8j位的磁矩可能具有最小值。

The electronic structure of NdFe10M2(M = Ti, V, Cr, Mn, Mo, M ) compounds was obtained by the LMTO(linear Muffin-tin orbit) method, and the micro magnetic properties wereexamined through the total density of state(TDOS) and the local density of state(DOS). Theacts suggest that the two mechanisms, which are responsible for variation in magnetic moments of NdFe10M2 with interstitial N(or C) atoms. The volume expansion leads to the enhanCement of Fe-Fe exchange interaction at 8i and 8f site, with the result that the magneticmoments at both the sites increase, meanwhile, the magnetic moments at 8j site decreases dueto the hydridization between 3d(Fe) and 2p(N or C) orbits.