1. Beijing National Laboratory for Molecular Sciences; Key Laboratory of Organic Solids; Institute of Chemistry; Chinese Academy of Sciences (ICCAS); Beijing 100190 P.R. China
2. College of Chemistry and Environmental Science; Hebei University; Baoding 071002 China
3. Molecular Materials and Nanosystems; Eindhoven University of Technology; P.O. Box 513 5600 MB Eindhoven The Netherlands
4. National Center for Nanoscience and Technology; Beijing 100190 China
5. Department of Materials Science and Engineering; College of Engineering; Peking University; Beijing 100871 China