Oxides and oxy-ions of the non-metals. Part XI. Electron spin resonance study of the BrO3 radical in γ-irradiated potassium bromate

Abstract

The radical BrO₃, produced by γ-radiolysis of potassium bromate at 77 K has been studied by e.s.r. At this temperature the magnetic parameters were: g₁₁2·027, g₂₂ 2·102 and g₃₃ 2·076, and A₁₁ 864, A₂₂ 483, and A₃₃ 483 G, and at ca. 130 K, the rotating radical gave g_av 2·070 and A_iso 614 G. On further warming, BrO₃ was lost, leaving a resonance assignable to O₃^–. The calculated spin-density on the Br atom and the p/s ratio follow the trend predicted from the results of the isoelectronic species AsO₃^2–, PO₃^2–, SeO₃^–, SO₃^–, and ClO₃. BrO₃ is also found to be a product of γ-irradiation of frozen alkaline solutions of potassium bromate.