SYNTHESIS AND CHARACTERIZATION OF ACTINIDE-EXCHANGED PREYSSLER HETEROPOLYANIONS [ANP(5)W(30)O(110)](N-) (AN=TH, AM, CM)

Interest in the use of heteropolyoxometalate clusters as actinide comp lexants motivates our studies of the Preyssler heteropolytungstate ani on, [NaP5W30O110](14-), and its actinide-exchanged derivatives, [AnP(5 )W(30)O(110)](n-). Under specific conditions, substitution of Na+ is p ossible by La3+ and Th4+ as well as by U4+ and the transuranics Am3+ a nd Cm3+. Both [AnP(5)W(30)O(110)](11-) (for An = Th4+, U4+) and [AnP(5 )W(30)O(110)](12-) (for An=Am3+, Cm3+) as well as [LaP5W30O110](12-) e xhibit remarkable redox properties and form heteropoly blues. Although similar, the electrochemistry of the An(3+)/La3+- and An(4+)-exchange d anions are different and distinguishable by cyclic voltammetry in aq ueous mineral acid electrolytes. The synthesis of the new Preyssler an ion complexes of La3+, Th4+, Am3+, and Cm3+ will be described along wi th results from cyclic voltammetry measurements. (C) 1998 Elsevier Sci ence S.A.