Ag_(12)Y团簇三种可能构型的电子结构和磁性研究

Research of the electron structure and magnetism of three Ag_(12)Y clusters

应用密度泛函理论和广义梯度近似方法研究Ag_(12)Y团簇的稳定性、电子结构和磁性,计算了键长、束缚能、最高占据轨道、最低占据轨道、磁矩和电子分布。结果表明:Ag_(12)Y团簇稳定性比对应的Ag_(13)团簇高,替代中心原子比替代表面原子更稳定,O_h构型的Ag_(12)Y为最稳定结构;计算的7个Ag_(12)Y团簇外层电子均为闭壳层结构,具有较好的化学稳定性;Ag_(12)Y磁性与替代原子位置和团簇对称性有关,I_h构型和替代表面原子形成的C_(5v)构型具有局域磁性,C_s、C_(2v)构型和替代中心原子形成的C_(5v)构型磁矩为0。

Based on the density functional theory and generalized gradient approximation method, The stability, electron structure and magnetism of three Ag12Y clusters were explored, and the bond length, binding energy, the highest occupied molecular orbit, the lowest occupied molecular orbit, the magnetic moment and electron distribution were calculated. The result shows that the Ag12Y clusters are more stable than the corresponding Ag13clusters, and the replaced central atoms are more stable than the surface atoms, too; the Ag13 Y with Oh structure is the most stable one; the outer- shell electron of the calculated seven Ag12Y cluster is closed shell structure, which has better chemic stability ; the magnetism of Agl2 Y is related to the position of the replaced atom and symmetry property of clusters ; C5v structure formed by Ih and the replaced surface atom is locally magnetic ; the magnetic moment of the Cs, C2v structure and C5v structure formed by the replaced central atom is zero.