1. Department of Physics and Organic and Carbon Electronics Lab (ORaCEL), North Carolina State University, Raleigh, North Carolina 27695, USA
2. Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico, 87545, USA
3. Department of Materials Science and Engineering and Organic and Carbon Electronics Lab (ORaCEL), North Carolina State University, Raleigh, North Carolina 27695, USA
4. Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, USA
5. Department of Physics and Astronomy, University of Utah, Salt Lake City, Utah 84112, USA
6. Department of Chemistry, University of Chicago, Chicago, Illinois 60637, USA
7. Argonne National Laboratory, Lemont, Illinois 60439, USA