用密度泛函理论研究ZrnB(n=1-13)团簇的结构及性质

利用密度泛函理论, 得到了ZrnB(n=1-13)团簇的基态结构, 计算并讨论了团簇能量的二阶差分和离解能. 结果表明, n=2, 5, 12时, 相应团簇较稳定, 特别是Zr5B团簇的稳定性最高. 同时分析了ZrnB团簇的电子性质及磁性, 结果显示能隙随n值的增大出现奇偶振荡趋势, 特别是Zr12B团簇的能隙只有0.015 eV, 表明该团簇已具有金属性. 电荷转移随n值增大, 整体呈增大趋势, 除了二聚体ZrB, 电荷由B原子转移到Zr原子. 利用Mulliken布居分析得到二聚体ZrB(5.000 μB)和团簇Zr4B(3.000 μB)的磁矩较大, ZrnB团簇中总磁矩主要来自Zr原子的4d轨道.

Study on Structures and Properties of ZrnB(n=1-13) Clusters Using DFT

The ground-state structures of ZrnB(n=1-13) clusters were determined by using density functional theory (DFT). The second-order energy differences and fragmentation energies of the ground-state structures were calculated and discussed. The results indicated that the relative stabilities of Zr2B, Zr5B, and Zr12B were stronger than these of other sized clusters, especially Zr5B cluster possessed the highest stability. The electronic properties and magnetism were analyzed. The results showed that the energy gap of clusters presented an odd-even oscillation tendency along with n increase, especially, the energy gap of Zr12B cluster was as small as 0.015 eV, implying that Zr12B cluster possessed metallic-like features. The charge transfer gradually strengthened along with the n increase. For ZrnB(n=1-13) clusters but n=1 (ZrB), we found charge transferred fromBto Zr site. The magnetic moment of ZrB(5.000 μB) and Zr4B(3.000 μB) were bigger andthe totalmagnetic moment of ZrnB clusters mainly came fromthe localed 4d orbital of Zr atom.