Studies of the halide complexation of element 105 in aqueous solution were performed on 34-s 262 Ha produced in the 249 Bk( ls O,5n) reaction. The 262 Ha was detected by measuring the fission and alpha activities associated with its decay and the alpha decays of its daughter, 4.3-s 258 Lr. Time-correlated pairs of parent and daughter alpha particles provided a unique identification of the presence of 262 Ha. About 1600 anion exchange separations of 262 Ha from HCl and mixed HC1/HF solutions

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... performed on a one-minute time scale. Reversed-phase micro-chromatographic columns incorporating triisooctyl amine (TIOA) on an inert support were used in the computer-controlled liquid chromatography apparatus, ARCA II. 262 Ha was shown to be adsorbed on the column from either 12 M HCl/0.02 M HF or 10 M HCl solutions like its homologs Nb and Ta, and like Pa. In elutions with 4 M HCl/0.02 M HF (Pa-Nb fraction), and with 6 M HNO3/O.OI5 M HF (Ta fraction), the 262 Ha activity was found in the Pa-Nb fraction showing that the anionic halide complexes are different from those of Ta, and are more like those of Nb and Pa. In separate elutions with 10 M HCl/0.025 M HF (Pa fraction) and 6 M HN0 3 /0.015 M HF (stripping of Nb) the 262 Ha was found to be equally divided between the Pa and Nb fractions. The non-tantalum like halide complexation of Ha is indicative of the formation of oxohalide or hydroxohalide complexes, like [NbOCU]" and [PaOCl 4 ] or [Pa(OH) 2 Cl 4 ]", at least for intermediate HCl concentrations, in contrast to the pure halide complexes in Ta, like [TaCl 6 ] -.