Vibrational energy transfer between DF(v=2) and CO2

Rates have been determined for the transfer of vibrational energy between DF(ν=2), DF(ν=1), and CO2 using a laser-induced fluorescence technique. DF, in DF--CO2 gas mixtures, was excited to both the ν=1 and ν=2 vibrational levels by absorption of radiation from a pulsed DF laser operating simultaneously on ν (1--0) and ν (2--1) transitions. By monitoring fluorescence intensity at 1.7, 3.5, and 4.4 μ, the temporal behavior of DF(ν=2), DF(ν=1), and CO2 (001) populations was followed. A computer program was used to solve the differential rate equations and a ''best fit'' with experimental data determined the rate parameters. Rate constants obtained in this manner from the fluorescence data are k=5.1times105 sec-1center-dottorr-1 for the DF(ν=2) →CO2 transfer and k=1.5times104 sec-1center-dottorr-1 for CO2 (001) deactivation by DF