1. Key Laboratory of Luminescence from Molecular Aggregates of Guangdong Province SCUT–HKUST Joint Research Institute State Key Laboratory of Luminescent Materials and DeviceSouth China University of Technology No. 381 Wushan Road, Tianhe District Guangzhou 510640 P. R. China
2. Beijing National Laboratory for Molecular Sciences (BNLMS)Institute of Chemistry, Chinese Academy of Sciences Beijing 100080 P. R. China
3. Department of PhysicsSchool of ScienceBeijing Jiaotong University Beijing 100044 P. R. China
4. Department of Chemistry and MOE Key Laboratory of Organic Optoelectonics and Molecular EngineeringTsinghua University Beijing 100084 P. R. China
5. Department of ChemistryHong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstructionand Institute for Advanced StudyThe Hong Kong University of Science and Technology Clear Water Bay Kowloon Hong Kong China