REACTION OF SULFUR HEXAFLUORIDE WITH HYDRATED ELECTRONS

The reaction of SF6 with eaq- in irradiated aqueous solutions leads to F-, SO42-, and H3O+ as stable products via an intermediate with oxidizing properties. The rate constant for this reaction has been determined to be k(SF6+eaq-) = 1.65 × 1010 M-1 sec-1. Since G(F-) = 16.55 was obtained in buffered (pH ∼6.5) solutions and the suggested mechanism requires the formation of 6F- from every molecule of SF6 in its reaction with eaq-, G(eaq-) = 2.76 was calculated. The yield of SO42- ion amounts to 1/6G(F-) and therefore is equal to the yield of eaq- which is scavenged by the SF6. The SO42- ion results from the reoxidation of the sulfur from a lower oxidation state. Owing, to the specificity of SF6 as an eaq- scavenger and the high F- yield, this system can be conveniently used for the determination of relative rate constants in eaq- scavenging competition studies.