Atomic structure and magnetism in small rhodium clusters

The atomic structure and magnetism in small Rh_n, n=2-13 clusters have been studied using the ab initio ultrasoft pseudopotential method and the generalized gradient approximation for the exchange-correlation energy. We find new structures for n=5, 7 and 8 clusters. Furthermore Rh₁₃ does not have any of the well known high symmetry structures (icosahedron, decahedron or cuboctahedron) to be of the lowest energy. All these clusters have large magnetic moments which oscillate in the range of 1-2 m_B/atom. These results will be discussed in the light of the available experimental data.