Yang Ji-Xian

First Principle Calculation on AunAg2 (n = 1 4) Clusters

The first-principles method based on density-functional theory is used to investigate the geometries of the lowest-lying isomers of AunAg2 (n = 1~4) clusters. Several low-lying isomers are determined, and many of them in electronic configurations with a high spin multiplicity. The stability trend of Ag-doped Aun clusters is compared to that of pure Aun clusters. Our results indicate that the inclusion of two Ag atoms in the clusters lowers the cluster stability, indicating higher stability as the structures grow in size. The bigger energy difference between the Aun and AunAg2 curves as the structures grows in size. This information will be useful to understanding the enhanced catalytic activity and selectivity gained by using silver-doped gold catalyst.

Quantum-Mechanical Study of Small Au2Pdn (n = 1～4) Clusters

Gold-doped palladium clusters, Au2Pdn (n = 1~4), are investigated using the density functional method B3LYP with relativistic effective core potentials (RECP) and LANL2DZ basis set. The possible geometrical configurations with their electronic states are determined, and the stability trend is investigated. Several low-lying isomers are determined, and many of them are in electronic configurations with a high-spin multiplicity. Our results indicate that the palladium-gold interaction is strong enough to modify the known pattern of bare palladium clusters, and the lower stability as the structures grow in size. The present calculations are useful to understanding the enhanced catalytic activity and selectivity gained by using gold-doped palladium catalyst.

Density functional study of AunCu (n = 1?7) clusters

The possible stable geometrical configurations and the relative stabilities of the lowest-lying isomers of copper-doped gold clusters, AunCu (n = 1–7), are investigated using the density functional theory. Several low-lying isomers are determined. The results indicate that the ground-state AunCu clusters have planar structures for n = 1–7. The stability trend of the AunCu clusters (n = 1–7), shows that odd-numbered AunCu clusters are more stable than the neighbouring even-numbered ones, thereby indicating the Au5Cu clusters are magic cluster with high chemical stability.