Giant magnetic moments of B and C doped cuboctahedral Mn13 clusters.

Using first-principles calculations based on gradient corrected density functional theory we show that an otherwise distorted icosahedric Mn(13) ferrimagnetic cluster, when doped with six B or C atoms, transforms into a ferromagnetic cuboctahedral cluster with a magnetic moment that is an order of magnitude larger than that of the pure Mn(13) cluster. The origin of this magnetic transition is attributed to the change in the Mn-Mn interatomic distance resulting from the structural transformation. These doped clusters remain ferromagnetic with giant moments even after the removal of a B or C atom. However, similar doping with N atom does not lead to ferromagnetic ordering and Mn(13)N(6) remains ferrimagnetic with a magnetic moment of only 3 μ(B), just as in its parent Mn(13) cluster.