1. Center for Polymers and Organic Solids Department of Chemistry and Biochemistry University of California at Santa Barbara Santa Barbara CA 93106 USA
2. Cavendish Laboratory University of Cambridge CB3 0HE Cambridge UK
3. Key Laboratory for Micro‐Nano Optoelectronic Devices of Ministry of Education School of Physics and Electronics Hunan University Changsha 410082 China
4. Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
5. Laboratory of Materials Science Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China