1. Organic Semiconductor Centre, EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife KY16 9ST, U.K.
2. Organic Semiconductor Centre, SUPA, School of Physics and Astronomy, University of St Andrews, North Haugh, St Andrews, Fife KY16 9SS, U.K.
3. Laboratory for Chemistry of Novel Materials, University of Mons, 7000 Mons, Belgium
4. Laboratoire de Chimie des Polymères Organiques, UMR 5629, University of Bordeaux, 33607 Pessac, France
5. Renewable Energy Research Institute, University of Castilla-La Mancha, Paseo de la Investigación 1, 02071 Albacete, Spain
6. Department of Physical Chemistry, University of Alicante, 03080 Alicante, Spain