1. Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, College of Chemistry, Jilin University, Liutiao Road #2, Changchun130061, P. R. China
2. School of Physics, Northeast Normal University, Changchun130024, P. R. China
3. State Key Laboratory and Institute of Elemento-Organic Chemistry, The Centre of Nanoscale Science and Technology and Key Laboratory of Functional Polymer Materials, College of Chemistry, Nankai University, Tianjin300071, China