1. Department of Inorganic and Analytical Chemistry University of Geneva 30 quai E. Ansermet 1211 Geneva 4 Switzerland
2. Laboratory of Crystallography University of Geneva 24 quai E. Ansermet 1211 Geneva 4 Switzerland
3. Laboratory of Coordination Chemistry (LCC) CNRS & Université de Toulouse (UPS, INP) 205 route de Narbonne Toulouse 31077 Cedex 4 France