Vibrational Relaxation of Oxygen

Abstract

The vibrational relaxation of oxygen has been studied by shock-tube interferometry from 600° to 2600°K with the result that at 1 atm pressure the relaxation time τv in seconds is found to be τv=1.49×10—10 exp (133T—½). The presence of up to 2% CO has no observable effect on this time. The previous experimental work of Blackman was probably influenced by impurities at the lower temperatures but the present results are in accord with his at the higher temperatures. Comparison is made with various theoretical calculations and the primary temperature dependence of T—½ is confirmed. It is further noted that Schwartz's Method A of matching the exponential interaction is in better accord with observations than Method B.