Oxygen Vibrational Relaxation in O2–He and O2–Ar Mixtures

Abstract

The vibrational relaxation time of oxygen in several mixtures of O2+He and O2+Ar has been determined by shock-tube interferometry. Using the previously determined data for O2–O2 collisions, the vibrational relaxation time for O2–He and O2–Ar collisions has been found. The latter is in agreement with Camac's determination and extends to somewhat lower temperatures. For oxygen infinitely dilute in helium, the vibrational relaxation time in atm·sec is given by pτv=5.3×10—9 exp(60T—½) from 400° to 1600°K.