1. Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand
2. Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark
3. Department of Chemistry, University of Waikato, Private Bag 3105, Hamilton 3240, New Zealand
4. Department of Chemistry, University of Guelph, N1G 2W1, Guelph, Ontario, Canada