▎ 摘 要
Mn-7 cluster on graphene with different structural motifs and magnetic orders are investigated systematically by first-principles calculations. The calculations show that Mn-7 on graphene prefers a two-layer motif and exhibits a ferrimagnetic coupling. The magnetic moment of the Mn-7 cluster increases from 5.0 mu(B) at its freestanding state to about 6.0 mu(B) upon adsorption on graphene. Mn-7 cluster also induces about 0.3 mu(B) of magnetic moment in the graphene layer, leading to an overall enhancement of 1.3 mu(B) magnetic moment for Mn-7 on graphene. Detail electron transfer and bonding analysis have been carried out to investigate the origin of the magnetic enhancement.