1. Argonne-Northwestern Solar Energy Research Center, Department of Chemistry and the Materials Research Center; Northwestern University; 2145 Sheridan Road Evanston IL 60208 USA
2. College of Materials Science and Opto-Electronic Technology, University of Chinese Academy of Sciences; No.19A Yuquan Road Beijing 100049 China
3. Department of Physical Chemistry; University of Málaga; Malaga 29071 Spain
4. Polyera Corporation; 8045 Lamon Avenue Skokie IL 60077 USA