Small clusters: Magnetic order and magnetic moment

The effects of a manganese atom on the magnetic order and magnetic moments of FenMn ( n = 1 – 12 ) clusters have been investigated using the all-electron density functional theory. The results reveal that the Fe–Mn couplings in the lowest-energy structures of FenMn ( n = 1 – 12 ) clusters undergo a change from ferromagnetic ordering for the smallest ( n = 1 , 2 ) clusters to ferrimagnetic ordering for the intermediate ( n = 3 – 6 ) clusters. Starting from n = 7 , however, ferromagnetic Fe–Mn couplings completely prevail. The low coordination number of the doped Mn atom results in it having a high spin moment in the Fe–Mn binary clusters, which exhibits a marked magnetic moment surface enhancement effect.