Giant magnetic moments of B and C doped cuboctahedral Mn13 clusters

Abstract

Using first-principles calculations based on gradient corrected density functional theory we show that an otherwise distorted icosahedric Mn₁₃ 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 Mn₁₃ 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 Mn₁₃N₆ remains ferrimagnetic with a magnetic moment of only 3 μ_B, just as in its parent Mn₁₃ cluster.