Chem. J. Chinese Universities ›› 2019, Vol. 40 ›› Issue (11): 2354.doi: 10.7503/cjcu20190300

• Physical Chemistry • Previous Articles     Next Articles

Theoretical Studies on the Zintl Crystals Assembled by Al6ONa2 Clusters

ZHANG Zhaoyan,CHEN Hongshan()   

  1. College of Physics and Electronic Engineering, Northwest Normal University, Lanzhou 730070, China
  • Received:2019-05-24 Online:2019-11-10 Published:2019-10-12
  • Contact: CHEN Hongshan E-mail:chenhs@nwnu.edu.cn
  • Supported by:
    ? Supported by the National Natural Science Foundation of China(11664034)

Abstract:

The low energy isomers of Al6ONa2 were determined by genetic algorithm combined with ab initio calculations. The results reveal the strong magic behavior of O-centered Al-Na cluster with 26 electrons. The interaction of atomic O orbitals and Jellium orbitals of the metal moieties forms bonding orbitals localized on O atom and antibonding orbitals delocalized on the whole cluster. The hetero metal cluster with 26 electrons form closed s 2p 6S 2P 6D 10 shells and corresponds to a strong magic structure. The Na + cations are ionically bonded to the Al6O 2- anion. The electronic structures of Al6O 2- core also accord with the Wade-Mingos rule. Based on the peculiar stability of the superatomic anion Al6O 2-, we predicted two AB2 clusters with Pn 3 ˉ m and Fd 3 ˉ m point groups by density functional theory(DFT) calculations. The binding energy of Al6ONa2 cluster is -23.44 eV, and the interaction energy between the clusters in the crystal structures is -1.19 and -1.53 eV. The electronic structures of the crystals indicate that both the assembled structures have semiconductor properties. The phonon dispersion curves and elastic constants show that the assembled crystals are dynamically and mechanically stability.

Key words: Magic cluster, Superatomic anion, Electronic structure, Cluster assemble

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