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采用局域密度近似下的密度泛函理论和原子轨道的线性组合方法,通过离散变分法自洽求解Kohn-Sham方程,详细地研究了FenB(n≤6)团簇的结构和磁性,所得主要结论如下:第一,B原子更倾向于在团簇的表面而不是在团簇的内部,通常计算非晶态的四面体结构和三棱柱结构,对于孤立团簇而言是不稳定的,这说明环境对团簇的结构稳定性有重要影响;第二,当Fen+1团簇中的一个Fe原子被B原子取代形成Fen团簇时,其结合能增大而Fe原子的磁矩减小;第三,Fe<In this paper, by using a linear combination of atomic orbitals approach with the density func-tional formalism, the stuctures and the magnetic properties of FenB clusters (n=1-6) have been studied in detail. It is found that the B atom is favored to locate at the surface not the center of the cluster, and the tetrahedron for Fe4B and the triangular prism for Fe6B clusters are not the most stable structures. When one atom in Fen+1 cluster is replaced by a B atom forming FenB cluster, the binding energy increases, while the moment of Fe atom decreases. The variation of average moment with the atomic percentage of B atom is nonlinear in FenB cluster, differing from the behavior of bulk amorphous Fe-B alloys. It is indicated that the environmemt and doping play an important role on the stability and magnetic properties of cluster.
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