1. Institute of Atomic and Molecular Physics
2. Sichuan University
3. Chengdu 610065
4. China
5. Department of Physics
6. Nanyang Normal University
7. Nanyang 473061
8. Department of Physics and High Pressure Science and Engineering Center
9. Department of Chemistry
10. University of Patras
11. GR-26500 Patras
12. Greece