Anomalous magnetism in small Mn clusters

Unlike any other transition metal clusters, and in sharp contrast to its bulk behavior, Mn clusters containing up to 5 atoms are found to retain their atomic magnetic moments. Mn2, Mn3, Mn4 and Mn5 clusters in their ground states are coupled ferromagnetically and carry a moment of 10, 15, 20 and 25 μB, respectively. Several low-lying excited states have also been identified. These results are based on all electron first-principles self-consistent calculations using density functional theory and generalized gradient approximation. Predictive capability of this approach is established by comparing the calculated energetics, electronic and magnetic properties of Mn2+ with experiment.