ELECTRONIC-STRUCTURE CALCULATIONS OF COBALT CLUSTERS

The electric structure and magnetic properties of small cobalt clusters (4 less-than-or-equal-to n less-than-or-equal-to 19) have been studied using the spin-polarized discrete variational method within the local-density-functional theory. The results show that the magnetic moment of the Co13 cluster converges to that of the bulk, the average moment of the cluster is in agreement with the experiment. The Co13 cluster with icosahedral symmetry has the highest magnetic moment among the 13-atom isomers. The atomic magnetic moments of cobalt clusters have been discussed, in particular, with reference to changing cluster size and interatomic distances. The cluster symmetry is an important factor for determining the magnetic moments of the clusters.