Abstract
When dilute solutions of
iodine in methyl iodide are irradiated with neutrons more than 56% of the radioactive
iodine-128 appears in organic combination. This increase arises from an isotope
exchange reaction with a rate independent of iodine concentration. When more
concentratedsolutions are irradiated
the organic radioactivity is reduced below 56% and the reduction depends on the
square root of iodine concentration. Results are examined in terms of the
kinetic theory of hot reactions and also a treatment for distinguishing between
'Rot' and 'hot spot diffusive'reactions.