1. Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
2. G. T. Seaborg Institute for Transactinium Science, Lawrence Livermore National Laboratory, Livermore, CA 94551, USA
3. Westinghouse Savannah River Company, Savannah River Technology Center, Aiken, SC 29808, USA
4. Washington State University, Department of Chemistry, Pullman, WA 99164, USA
5. Forschungszentrum Rossendorf e.V., Institut für Radiochemie, Postfach 51 01 19, D-01314 Dresden, Germany