1. Department of Chemistry, Rice University, 6100 Main Street, Houston, Texas 77005, United States
2. Department of Electrical and Computer Engineering, Rice University, 6100 Main Street, Houston, Texas 77005, United States
3. ARC Centre of Excellence in Exciton Science, School of Mathematics and Statistics, University of Melbourne, Melbourne, Victoria 3010, Australia
4. Department of Chemistry and Biochemistry, University of Massachusetts Dartmouth, 285 Old Westport Road, North Dartmouth, Massachusetts 02747, United States