Structures and electronic properties of small FeBn (n=1-10) clusters

The geometries, stabilities, electronic properties, and magnetism of FeBn clusters up to n=10 are systematically studied with density functional theory. We find that our optimized structures of FeB2, FeB3, FeB4, and FeB5 clusters are more stable than those proposed in previous literature. The results show that it is favorable for the Fe atom to locate at the surface, not at the center of the cluster, and that FeB4 and FeB9 clusters exhibit high stability. For all the FeBn clusters studied, we find the charge transfer from Fe to B site and the coexistence of ionic and covalent bonding characteristics. The computed total magnetic moments of the lowest-energy structures oscillate with the cluster size and are quenched at n=4, 6, 8, and 10.