1. NMR Research Group, Department of Physics,
University of Oulu, P.O. Box 3000, FIN-90014 Oulu, Finland
2. NMR Laboratory, Institute of
Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v. v. i., Flemingovo nám.
2, CZ-16610 Prague 6, Czech Republic
3. Department of Chemistry, Durham University, Durham, DH13LE, United Kingdom