钯团簇掺杂钇原子的密度泛函研究

在相对论有效原子实势近似下,用密度泛函方法(B3LYP/LANL2DZ)计算了二元合金团簇PdnY(n=1-5)可能的几何构型和对应的电子态,得到一系列稳定异构体的结构参数、电子态、能量和谐振频率.用最高占据轨道(HOMO)与最低空轨道(HOMO)之间的能级间隙描述团簇的稳定性,Pd2Y团簇的能级间隙最大,PdY团簇的能级间隙最小.Pd-Y相互作用改变了纯钯团簇的几何构形和稳定性.计算结果对系统研究Pd-Y体系的物理化学性质具有意义.

Density Functional Study of PdnY (n=1-5) Clusters

The geometries of the lowest-lying isomers of the PdnY (n=1-5) clusters were investigated using the density-functional method B3LYP with relativistic effective core potentials (RECP) and the LANL2DZ basis set. The HOMO-LUMO gap has been used to characterize the cluster stability. Large HOMO-LUMO gap is found for Pd2Y with triangular structure, while it is much smaller in the PdY cluster. The results show that the palladium-yttrium interaction is strong enough to modify the known pattern and stability of bare palladium clusters. This information will be useful for a systematical understanding of the physicochemical properties of the Pd-Y system.