Vibrational relaxation of UF6: Ultrasonic measurements in mixtures with Ar and N2thinsp;

摘要

Ultrasonic attenuation has been measured in neat UF6and in mixtures of 5percnt; and 10percnt; UF6in Ar and N2at 273 and 323 K. In all cases a single relaxation process was observed and attributed to relaxation of the total UF6vibrational energy. Isothermal relaxation times were in the range (4ndash;17) times;10minus;9atmthinsp;s. The vibrational relaxation rate inferred for UF6ndash;N2collisions shows a slight negative temperature dependence, while the rates inferred for UF6ndash;UF6and UF6ndash;Ar collisions are virtually independent of temperature over the range of these experiments. In this range, Ar and N2are slightly less efficient collision partners (by factors of sim;1.5ndash;3.0) than UF6itself.