Oxides and oxyions of the non-metals. Part XV. Electron spin resonance spectra of some selenium and bromine radicals

Abstract

Exposure of various crystalline bromates to ⁶⁰Co γ-rays at 77 K gave radicals identified by their e.s.r. spectra as BrO₂ and BrO₃. Barium sulphate doped with bromate gave BrO₃ together with another bromine-containing radical tentatively identified as BrO₃^2–. Frozen aqueous glasses containing bromate ions gave only BrO₂ on irradiation and annealing.

Similar treatment of selenates gave the radicals SeO₂^–, SeO₃^–, and SeO₄^–, together with the previously unknown radical SeO₄^3–. The latter was formed predominantly when aqueous glasses containing selenate ions were irradiated at 77 K. They were also formed in aqueous selenite glasses.

The electronic structures of these radicals are discussed in the light of these results and compared with those for other isoelectronic species.