GEOMETRY, ELECTRONIC-STRUCTURE, AND MAGNETISM OF SMALL NI-N (N=2-6, 8, 13) CLUSTERS

Electronic structure, geometries, and magnetic moments of small Ni-n ( n = 2-6, 8, 13) clusters have been studied using a linear combination of atomic orbital-molecular orbital approach within the density functi onal formalism. The clusters are found to exhibit an abundance of elec tronic states corresponding to different geometries and spin multiplic ities close to their ground states. Ni-4 has two isomers with differen t geometries. All the clusters have finite total spins but the moment per atom varies considerably with size. Ni-4 and Ni-5 are found to hav e abnormally large magnetic moments per atom and Ni-5 is a magnetic ma gic number.