1. Department
of Chemistry and Biochemistry University of Arizona, 1306 E. University
Boulevard, Tucson, Arizona 85721, United States
2. Department
of Physics and Astronomy, University of Denver, Denver, Colorado 80208, United States
3. National Renewable Energy Laboratory, Golden, Colorado 80401, United States
4. School
of Chemistry and Biochemistry and Center for Organic Photonics and
Electronics, Georgia Institute of Technology, Atlanta, Georgia 30332, United States