Abstract
We investigate magnetic and structural properties of Fe-55 clusters from DFT calculations. Previous calculations indicate the existence of icosahedral clusters with two antiferromagnetic states with magnetic moments smaller than experimentally measured. In the present work, we find a rearrangement of the atoms of the core (the 13 saturated atoms) that tend to form a structure close to a cuboctahedron, preserving the icosahedral structure for the surface shell (the 42 surface atoms). The introduction of a Hubbard correction term leads for the most stable electronic state to a ferromagnetic state and a high magnetic moment in agreement to experiment. (C) 2012 Elsevier B. V. All rights reserved.