1. Department of General and Inorganic Chemistry, Faculty of Chemical Technology, University of Pardubice, Čs. legií 565, CZ-532 10, Pardubice, Czech Republic, Faculty of Natural Science, Charles University in Prague, Hlavova 2030, 128 40 Praha 2, Czech Republic, and Institute of Inorganic Chemistry, Academy of Science of the Czech Republic, 250 68, Řež, Czech Republic