Mg_mB_n团簇层状结构的密度泛函理论研究

Density Functional Theory of Tier-Like Structure of Mg_mB_n Clusters

用密度泛函理论(DFT)中的杂化密度泛函B3LYP方法,在6-31G*水平上对Mg2B6、Mg4B10、Mg6B13和Mg8B16团簇的层状结构进行了几何结构优化,并在同一水平上计算了其电子结构、振动特性和成键特性。结果表明:团簇中Mg-B键长在0.225~0.235nm,B-B键长在0.154~0.191nm;Mg原子的自然电荷在+1.24^+1.45e之间,B原子的自然电荷在–0.29~–1.10e之间;Mg4B10团簇有相对较高的动力学稳定性。

The equilibrium geometries, the electronic structures, the vibration properties and the bond properties of the tier-like structures of Mg2B6, Mg4B10, Mg6B13 and MgsB16 clusters have been studied by the hybrid density functional B3LYP on the 6-31G^＊ level. The calculated results show that the bond lengths are about 0.225~0.235 nm for Mg-B and 0.154-0.191 nm for B-B; the natural charge of B atoms is about -0.29-1.10 e by population analysis and about ＋1.24-＋1.45 e for Mg atoms; and the dynamic stabilities of Mg4B10 clusters are higher than that of other clusters.