Structures, binding energies and magnetic moments of small iron clusters: A study based on all-electron DFT

The structures, binding energies, and magnetic moments of FeN(N=2–13,15,19) clusters have been obtained by all-electron density functional theory. The Jahn–Teller effect plays an important role in determining the ground state of certain geometric structures. For Fe3 and Fe4, new ground states are found. The results indicate that the magnetic moment per atom shows only small variations with cluster size and remains in the vicinity of 3.0μB/atom over this size range. With increasing atom number the mean binding energy monotonically decreases and the second derivative of the binding energy indicates that N=6N=6 and N=10N=10 are magic numbers for neutral FeN clusters.