1. School of Materials Science and Engineering, National Institute for Advanced Materials, Nankai University, Tianjin 300350, P. R. China
2. Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
3. Department of Chemistry and Department of Computer Science, University of Toronto, Toronto, Ontario M5S 3H6, Canada
4. Tianjin Key Laboratory of Metal and Molecule-Based Material Chemistry, Nankai University, Tianjin 300350, P. R. China
5. Tianjin Key Laboratory for Rare Earth Materials and Applications, Nankai University, Tianjin 300350, P. R. China