Sc_(13)团簇的稳定性和磁性研究

The study on the stability and magnetism of Sc_(13) cluster

使用梯度修正的密度泛函理论,对Sc_(13)团簇的稳定性和磁性进行了广泛的研究.与邻近钪团簇,或者与其它13-原子3d过渡金属团簇相比,Sc_(13)团簇的基态结构二十面体具有最高对称性,结构和磁性均表现出高的稳定性.由于二十面体的高对称性,Sc_(13)团簇的对称性分子轨道为晶体场分裂壳层9A_g(1),10T_(1u)(3),8H_g(5),10A_g(1),6T_(2u)(3),11T_(1u)(3),3G_g(4),3G_u(4),and 9H_g(5).20个价电子以类似于凝胶模型的1S^21P^61D^(10)2S^2壳层填充前四组壳层,其余19个价电子依据洪德法则填充后五组壳层,从而产生了19.0μB的磁矩.5个半填充的晶体场分裂壳层与离域价电子填充的1S^21P^61D^(10)2S^2类壳层导致了稳定的高磁矩Sc_(13)团簇.

A comprehensive investigation on the stability and magnetism of Sc13 cluster is performed using a gradient - corrected density functional theory method. The ground state structure Ih - icosahedron of Sc13 has the highest symmetry and exhibits high structure stability and magnetic state, compared with the neighbor scandium clusters and any other 3d - transition metal 13 - atom clusters. Due to the high symmetry of an icosabedron, the symmetric molecular orbitals （MOs） of Sci3 is a sequence of crystal field splitting shells 9Ag （1） , 10T1u （3）, 8Hg（5）, 10Ag（1）, 6T2u（3）, 11T1u（3）, 3Gg（4）, 3Gu（4）, and9Hg（5）. The 20 valence electrons fill the first four group shells similar to the pattern of 1S^21P^61D^102^S^2 of Jellium model. The remaining 19 valence electrons fill the latter five group shells in complete accordance with Hund＇ s rule, and breed a magnetic moment of 19.0 μB. Five half filled crystal field splitting shells along with filled 1S^21P^61D^102^S^2 - like shells of delocalized electrons lead to a stable magnetic system.