1. School of Chemistry and Biochemistry and Centre for Organic Photonics and Electronics, Georgia Institute of TechnologyAtlanta, GA 30332-0400, USA
2. CEA-Saclay, Laboratoire Nanostructures et Semi-Conducteurs Organiques, CNRS-CEA-UPMC, SPCSI/DRECAM91191 Gif-sur-Yvette, France
3. Department of Chemistry, The University of ArizonaTucson, AZ 85721-0041, USA
4. Service de Chimie des Matériaux Nouveaux, Université de Mons-HainautPlace du Parc 20, 7000 Mons, Belgium