Magnetic properties of small vanadium clusters

The magnetism of small free vanadium clusters (V-N, N less than or equal to 59) with a bcc-like structure is studied using a d electron tight binding Hamiltonian. The spin density distribution is calculated self-consistently in the unrestricted Hartree-Fock approximation. We have found that the free V clusters shown different magnetic behavior depending on their size. Results for the local magnetic moments, average magnetic moment and the magnetic order at T = 0 K are obtain as a function of N. For the V-N clusters mu(avg) varies as a function of N due to the interplay between the changes in coordination number and local environment; for N less than or equal to 4 the ground state is ferromagnetic whereas for N greater than or equal to 9 the ground state is mainly antiferromagnetic in agreement with ab initio and tight binding calculations, respectively. (C) 2003 Published by Elsevier B.V.