1. Department of Chemistry and Biochemistry; University of Arizona; 1306 E. University Blvd. Tucson AZ 85721 USA
2. School of Mechanical Engineering and Center for Organic Photonics and Electronics; Georgia Institute of Technology; Atlanta GA 30332 USA
3. National Renewable Energy Laboratory; National Center for Photovoltaics; Golden CO 80401 USA
4. Stanford Linear Accelerator Campus; Stanford Synchrotron Laboratory; Menlo Park CA 94025 USA
5. Department of Physics; University of Arizona; 118 E. Fourth St. Tucson AZ 85721 USA