1. Center for Supramolecular Chemistry & Catalysis and Department of Chemistry, College of Science, Shanghai University, 99 Shang-Da Road, Shanghai 200444, P. R. China
2. Department of Physics, College of Science, Shanghai University, 99 Shang-Da Road, Shanghai 200444, P. R. China
3. The Skaggs Institute for Chemical Biology and Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States