Experimental Measurements of the Resonant Vibrational Energy Transfer between Mode v3 of CO2 and N2

The rate of the resonant vibration–vibration energy‐transfer process between mode ${\nu }_3$ of CO₂ and N₂ has been measured from 450°‐2600°K by monitoring the infrared emission from mode ${\nu }_3$ at 4.26 $\mu$ 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.