1. Institute for Inorganic Chemistry, University of Erlangen‐Nürnberg, Egerlandstr. 1, 91058 Erlangen, Germany, Fax. (internat.) + 49‐(0)9131/8527387
2. Department of Chemistry, Faculty of Science, Ain Shams University, Cairo, Egypt
3. Department of Chemistry and Biochemistry, Ohio University, Athens, Ohio 45701, USA