1. Materials
and Environmental Chemistry, Stockholm University, SE-106 91 Stockholm, Sweden
2. Swedish
NMR Centre, University of Gothenburg, Box 465, SE-405 30 Göteborg, Sweden
3. Department
of Chemistry and Biomolecular Sciences, Australian Research Council
Centre for Nanoscale Biophotonics, Macquarie University, Sydney, New South Wales 2109, Australia