1. Institute of Atomic and Molecular Physics
2. Sichuan University
3. Chengdu 610065
4. China
5. Beijing Computational Science Research Center
6. Beijing 100084
7. State Key Laboratory of Superhard Materials
8. Jilin University
9. Department of Physics
10. Nanyang Normal University
11. Nanyang 473061
12. Department of Chemistry
13. University of Patras
14. GR-26500 Patras
15. Greece