1. Beijing National Laboratory for Molecular Sciences CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of Sciences Beijing 100190 P. R. China
2. University of Chinese Academy of Sciences Beijing 100049 P. R. China
3. School of Materials Science and Engineering Tianjin Key Laboratory of Molecular Optoelectronic Sciences Tianjin University and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Tianjin 300350 P. R. China
4. School of Physics State Key Laboratory of Crystal Materials Shandong University Shandong 250100 P. R. China