1. Department of Chemistry, Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China, Department of Chemistry, Faculty of Science, Chiba University, Yayoi-cho, Inage-ku, Chiba 263-8522, Japan, and State Key Laboratory of Structural Chemistry, Fujian Institute of Research of Structure of Matter, Chinese Academy of Science, Fuzhou, Fujian 350002, P. R. China