Vibration-to-Vibration Energy Transfer of CO2(0001) with N2 and CO at Low Temperatures

The 4.3 µm fluorescence from CO 2 (00°1) induced by the pulsed irradiation of the HBr laser line of P -2 (6) transition has been measured in the CO 2 –N 2 and CO 2 –CO mixtures at 300∼150K. The analysis based on the mechanism including the inter- and intra-molecular vibration-to-vibration (V–V) energy transfers of CO 2 (00°1) gives the rates for respective processes. The observed V–V rate between CO 2 (00°1) and N 2 shows a negative temperature dependence, and agrees with a simple extrapolation of the data at higher temperatures as well as the calculation by the Sharma-Brau theory. Contrary to this, the intermolecular V–V rate between CO 2 (00°1) and CO attains a minimum at a temperature around 300K. The intramolecular V-V rate could be determined only for the mixture of CO 2 and N 2 ; the temperature dependence of the rate was reduced at lower temperatures and this was a phenomenon common to the CO 2 (00°1) deactivation in inert monoatomic gases.