First-Principles Study of Magnetic Properties of TM_13 and TM_13@Au_32 Clusters (TM=Mn, Co)

The structural and magnetic properties of TM_13 and TM_13@Au_32 clusters (TM=Mn, Co) are studied by first-principles calculations. We find that the Au_32 cluster can tune not only the magnetic moment but also the magnetic coupling properties between the TM atoms of the TM cluster. The Au_32 cluster can increase the net magnetic moment of Mn_13 clusters while reducing that of Co_13 clusters. The interaction between Au and Mn atoms induces more Mn atoms to form spin parallel coupling, resulting in an increase of the total magnetic moment of Mn_13 clusters, while for the Co_13 clusters, the interaction between Au and Co atoms does not change the magnetic coupling states between the Co atoms, but reduces the magnetic moment of the Co atoms, leading to a decrease of the total magnetic moment of this system. Our findings indicate that the encapsulation of Au_32 clusters can not only raise the chemical stability of TM clusters, but also can tune their magnetic coupling properties and magnetic moment, which enables such systems to be widely applied in fields of spintronics and medical science.