1. School of Biomolecular and Biomedical Sciences, Centre for Synthesis and Chemical Biology, Conway Institute for Biomolecular and Biomedical Research, Ardmore House, National University of Ireland, University College Dublin, Belfield, Dublin 4, Republic of Ireland, Institute for Technical and Macromolecular Chemistry, University of Hamburg, Bundesstrasse 45, 20146 Hamburg, Germany, and Materials Ireland Polymer Research Center, School of Physics, Trinity College, University of Dublin, Dublin-2, Ireland