Acta Phys. -Chim. Sin. ›› 2011, Vol. 27 ›› Issue (05): 1068-1074.doi: 10.3866/PKU.WHXB20110438

• THEORETICAL AND COMPUTATIONAL CHEMISTRY • Previous Articles     Next Articles

Density Functional Theory Study of Atomic and Molecular Oxygen Adsorption on Au Clusters

GUO Xiao-Wei, TENG Bo-Tao, YUAN Jin-Huan, ZHAO Yun, ZHAO Yue, LIU Sha   

  1. Institute of Physical Chemistry, Zhejiang Normal University, Jinhua 321004, Zhejiang Province, P. R. China
  • Received:2010-11-04 Revised:2011-01-19 Published:2011-04-28
  • Contact: TENG Bo-Tao E-mail:tbt@zjnu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (20903081) and Natural Science Foundation of Zhejiang Province,China (Y407163).

Abstract:

The adsorption behaviors of O and O2 on charged and neutral Au19 and Au20 clusters were systematically investigated by density functional theory (DFT) with Dmol3 program. Our results indicate that the adsorption energies of O on the hollow sites of Au19 are higher than those on Au20; while those on the side-bridge sites of the Au19 and Au20 clusters are similar. For negatively charged clusters, the adsorption energies of O and O2 are higher than those for neutral and positive clusters. The O―O bond lengths of the adsorbed O2 on the Au19 and Au20 clusters with different charges show a similar trend to the adsorption energy, that is, the O―O bond lengths on Au19- are longer than those on the Au19 and Au19+ clusters. Population analysis shows that more electrons transfer to the adsorbed O and O2 from the Au19- and Au-20 clusters, which indicates stronger interactions compared with the neutral or positive clusters. Charge density difference (CDD) analysis for O2 on the Au19 and Au20 clusters suggests that electrons of the Au19 and Au20 clusters transfer to the π* orbital of O2, upon which the O―O bonds are activated. The dissociation reaction barrier of O2 on Au19- is 1.33 eV, which is lower than those on Au19 (1.86 eV) and Au19+ (2.27 eV).

Key words: Oxygen atom and molecule, Adsorption, Reaction, Au cluster, Density functional theory

MSC2000: 

  • O641