1. Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education, Department of Chemistry, Tsinghua University, Beijing 100084, People’s Republic of China, Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Engineering Plastics (KLEP), Institute of Chemistry, Chinese Academy of Sciences (CAS), Beijing 100190, People’s Republic of China, Department of Chemistry, Drexel University, Philadelphia, Pennsylvania 19104, and Department of Polymer Science...