THE STRUCTURES AND MAGNETIC-PROPERTIES OF SMALL FENB CLUSTERS

The geometric structures and magnetic properties of small FenB cluster s have been studied by using a linear combination of atomic orbitals a pproach with the density functional formalism, and the Kohn-Sham equat ion is solved self-consistently by the discrete variational method. It is found that it is favourable for the B atom to locate at the surfac e, not at the centre of the cluster, and that the tetrahedron for Fe4B and the triangular prism for Fe6B clusters are not the most stable st ructures. When one atom in an Fe-n+1 cluster is replaced by a B atom, forming an FenB duster, the binding energy increases, while the moment of the Fe atom decreases. It is indicated that the environment and do ping play important roles as regards the stability and magnetic proper ties of clusters.