Fluorido complex formation of element 104, rutherfordium (Rf)

Ishii, Yasuo; Toyoshima, Atsushi; Tsukada, Kazuaki  ; Asai, Masato  ; Li, Z.*; Nagame, Yuichiro ; Miyashita, Sunao*; Mori, Tomotaka*; Suganuma, Hideo*; Haba, Hiromitsu*; Goto, Shinichi*; Kudo, Hisaaki*; Akiyama, Kazuhiko*; Oura, Yasuji*; Shinohara, Atsushi*; Schdel, M.; Pershina, V.*; Kratz, J. V.*

The cation-exchange behavior of element 104, rutherfordium (Rf), was investigated together with its lighter group-4 homologues Zr and Hf, and the tetravalent pseudo-homologue Th in HF/HNO mixed solution. The results demonstrate that distribution coefficients () of Rf in HF/0.10 M HNO decrease with increasing concentration of the fluoride ion [F], indicating the consecutive formation of fluorido complexes of Rf. We also measured the values of Rf and the homologues as a function of the hydrogen ion concentration [H]. The log values decrease linearly with an increase of log [H] with slopes between -2.1 and -2.5. This indicates that these elements are likely to form the same chemical compounds: mixture of [MF] and [MF] (M = Rf, Zr, Hf and Th) in the studied solution. It is also ascertained that sequence in the fluoride complex formation is Zr Hf Rf Th.