1. Faculty of Chemistry and Chemical Engineering, Yunnan Normal University, Kunming 650092, Yunnan, P. R. of China
2. School of Chemistry, University of Wales, Bangor, Gwynedd, LL57 2UW, U.K.
3. Global Institute Of Computational Molecular and Materials Science (GIOCOMMS), Toronto/Budapest/Beijing
4. College of Chemistry, Beijing Normal University, Beijing 100875, P. R. of China