GIANT MAGNETIC-MOMENTS IN 4D CLUSTERS

Electronic structure of 13-atom clusters of 4d nonmagnetic solids Pd, Rh, and Ru has been studied using a linear combination of atomic orbit als molecular-orbital approach within the density functional formalism . Pd13, Rh13, and Ru13 are all found to have nonzero magnetic moments. Unexpectedly, the ground state of Rh13 is found to have 21 unpaired e lectrons and thus a magnetic moment of 21 mu(B). These 4d-element magn etic moments are a result of the reduced dimensionality and the enhanc ed electronic degeneracy due to the symmetry of the cluster. The effec t of impurities on the moments is examined through calculations on FeP d12, FeRh12, RhPd12, and RuPd12 clusters.