Abstract:
Uranium hexafluoride molecules were photolysed in the presence of hydrogen by focused radiation of a repetitively pulsed CF4 laser (λ = 16 μm) with an energy of ~100 mJ per pulse at a pulse repetition rate 2 — 3.5 Hz. In the presence of hydrogen the yield of the photolysis of UF6 molecules was an order of magnitude higher than without hydrogen and the number of molecules photolysed per pulse was 3 — 5.5 times higher than their number in a zone where the radiation density exceeded the dissociation threshold. This effect was attributed to laser activation of UF6 molecules inside and outside this zone, and to a subsequent reaction of the activated molecules with hydrogen. In the presence of hydrogen the yield of the photolysis of UF6 molecules decreased from pulse to pulse practically proportionally to the change in the density of UF6 molecules, which was the result of reactions of the newly formed hydrogen radicals with activated and nonactivated UF6 molecules, and the rates of these reactions depended quadratically on the UF6 density before each pulse.