1. School of Chemistry and Biochemistry Center for Organic Photonics and Electronics Georgia Institute of Technology Atlanta GA 30332‐0400 USA
2. Department of Materials Science and Engineering North Carolina State University Raleigh NC 27606 USA
3. Stanford Synchrotron Radiation Lightsource SLAC National Accelerator Laboratory Menlo Park CA 94025 USA
4. Department of Physics North Carolina State University Raleigh NC 27606 USA
5. School of Chemistry and Biochemistry and School of Materials Science and Engineering Center for Organic Photonics and Electronics Georgia Tech Polymer Network Georgia Institute of Technology Atlanta GA 30332 USA