Unstable intermediates. Part LXXXVII. The dipositive radical cations of gallium, thallium, and mercury derived from aqueous solutions of gallium(III), thallium(III), and mercury(II) salts at 77 K by γ-irradiation
Highfield hyperfine features associated with 69Ga, 71Ga, 205Tl, 199Hg, and 201Hg which appear in the e.s.r. spectra of frozen aqueous solutions of salts of these metals after exposure to 60Co γ-rays show conclusively that the ions Ga2+, Tl2+, and Hg+ are formed. Hyperfine coupling constants and g-values are reported, together with results from annealing experiments. Both thallium-(I) and -(III) salts gave Tl2+ ions, with indistinguishable magnetic parameters despite the difference in starting material.