ELECTRONIC-STRUCTURE AND MAGNETISM OF SMALL V AND CR CLUSTERS

The electronic structure and magnetism of V-9, V-15, Cr-9, and Cr-15 clusters having body centered cubic (bcc) geometry have been studied using a Gaussian orbital basis and the local spin density approximation. For V-9 and Cr-9, calculations were made for several different lattice spacings. Our calculated moment of 0.33 mu(B) of V-9 is much smaller than the previously calculated 2.89 mu(B) and is in very good agreement with a recent experiment. Our calculated moments of 0.67 mu(B), 0.07 mu(B), and 0.40 mu(B), respectively for Cr-9, V-15, and Cr-15 at the 0 K bulk lattice spacing are also in good agreement with experiment. But Cr-9 was found to have a transition near the bulk lattice spacing such that the moment becomes very large above the room temperature lattice spacing. Calculations of V-9 and Cr-9 at various interatomic distances show that they go through small magnetic moment to large moment transitions at certain distances, similar to the nonmagnetic to magnetic transition in bulk phase. The density of states profiles of V-15 and Cr-15 show the features characteristic of the bulk as had been the case in our previous calculations of Fe, Ni, and Cu.