https://doi.org/10.1140/epjp/i2017-11427-7
Regular Article
Probing structure, electronic property, and hydrogen adsorption for the alkali auride series
1
School of Science, East China University of Technology, 330013, Nanchang, China
2
Software college, East China University of Technology, 330013, Nanchang, China
* e-mail: scu_lyf@163.com
Received:
3
October
2016
Accepted:
2
March
2017
Published online:
10
April
2017
The structural evolution, relative stability, electronic property, and hydrogen adsorption of the alkali auride series, AunM (
), 
, Na, K, Rb, Cs), have been investigated using the density functional theory calculations at PW91 level. For the lowest-energy clusters, the dopant atom M prefers to occupy a peripheral or capped site in the host, and M-induced geometries become three-dimensional more easily. The average binding energy per atom, fragmentation energy, second-order difference of energy, and HOMO-LUMO energy gap show a pronounced odd-even oscillation with the number of Au atoms, and the enhanced relative stabilities are found in Au5M (, Na, K) and Au3M (
, Cs) clusters. In these clusters, the H2 molecule would like to bond with Au atom rather than impurity atom. After adsorption, the AunM structures and H2 molecule in all AunM-H2 clusters are hardly perturbed and still maintain their structural integrity. The geometrical and energetic information indicates a weak adsorption of H2 molecule.
© Società Italiana di Fisica and Springer-Verlag Berlin Heidelberg, 2017
