Contribution from the Institut de Chimie de Rennes, UMR 6509 and UMR 6510, and the Groupe Matière Condensée et Matériaux, UMR 6626, CNRS-Université de Rennes1, Campus de Beaulieu, 35042 Rennes, France, and Department of Inorganic Chemistry, Budapest University of Technology and Economics, H-1521 Budapest, Gellért tér 4, Hungary(2004-04-21時点)
