Startup of transactinide chemistry in JAERI

The transactinide nuclides (261)Rf and (262)Db have been successfully produced in the (24)8CM(O-18,5n) reaction at 99 MeV and in the Cm-248(F-19,5n) reaction at 100, 103, and 106 MeV, respectively, at the JAERI tandem accelerator. The on-line ion exchange experiments with an automated fast and repetitive liquid chromatography separation system were performed in the HNO3/HF system using Rf homologues Zr-89m and Hf-167,Hf-165 produced in the Y-89(p, n) and Gd-152(O-18,xn) reactions, respectively. The radiotracers Zr-88, Hf-175, and Th-234 were also prepared and the distribution coefficients on ion exchange resins were measured systematically in 1-11 M HCl and 1-14 M HNO3 with the batch method. It was found that anion exchange experiments of Rf in 8 M HNO3 and 9 M HCl provided information useful to extract the ionic radius of Rf and to verify the influence of relativistic effects.