EXPERIMENTAL MEASUREMENTS OF RESONANT VIBRATIONAL ENERGY TRANSFER BETWEEN MODE NU3 OF CO2 AND N2

The rate of the resonant vibration-vibration energy-transfer process between mode v3 of CO2 and N2 has been measured from 450°-2600°K by monitoring the infrared emission from mode v 3 at 4.26 μ behind incident shocks in CO2-N2 gas mixtures. The data are shown to be in agreement with recent laser fluorescent measurements from 300°-1000°K. The combined data for the probability per collision are compared to theoretical calculations and indicate that below 1000°K the interaction is dominated by long-range forces and a probability inversely proportional to temperature is obtained, while above 1000°K the probability increases with temperature and the interaction is due to short-range forces.