1. Department of Chemistry, “Sapienza” University of Rome, P.O. Box 34-Roma 62, Piazzale A. Moro 5, I-00185 Roma, Italy
2. Faculty of Engineering, Østfold University College, P.O. Box 700, 1757 Halden, Norway
3. Institute for Energy Technology, P.O. Box 40, N-2027 Kjeller, Norway
4. Division of Physical Chemistry, Department of Chemistry, Lund University, P.O. Box 124, SE-221 00 Lund, Sweden
5. Department of Chemistry, University of Oslo, P.O. Box 1033, Blindern, N-0315 Oslo, Norway