1. Laboratory of Organic Solids; Institute of Chemistry; Chinese Academy of Science (ICCAS); Beijing 100190 China
2. Tianjin Key Laboratory of Molecular Optoelectronic Sciences; Department of Chemistry; School of Science; Tianjin University & Collaborative Innovation Center of Chemical Science and Engineering (Tianjin); Tianjin 300072 China
3. Department of Chemistry and Department of Physics; National University of Singapore; 3 Science Drive 3 117543 Singapore Singapore