1. Section of Inorganic and Analytical Chemistry, Department of Chemistry, University of Ioannina, 45110 Ioannina, Greece
2. Chemistry Department, M.V. Lomonosov Moscow State University, Leninskie Gory, Moscow, Russia
3. Medical Physics Laboratory, Medical School, University of Ioannina, 45110 Ioannina, Greece
4. X-ray Unit
5. Department of Chemistry, University of Cyprus, 1678 Nicosia, Cyprus
6. Department of Chemistry, McGill University, 801 Sherbrooke Street West, Montreal, Quebec H2A 2K6, Canada
7. Katholieke Universiteit Leuven, Rega Institute for Medical Research, Minderbroedersstraat 10, B-3000 Leuven, Belgium