Multilevel Vibrational−Vibrational (V−V) Energy Transfer from CO(v) to O2 and CO2

Abstract

The vibrational−vibrational (V−V) energy transfer from excited CO(v ≤ 10) to O2 and CO2 molecules was studied by laser-induced chemiluminscence/time-resolved Fourier transform infrared emission spectroscopy. The vibrationally excited CO molecules were produced by 193 nm photolysis of a mixture of CHBr3 and O2. The temporal populations of the 10 vibrational states of CO were obtained from the time-resolved IR emission spectra. The rate equations were solved by a differential method we have suggested. Nine vibrational quenching rate constants kv (v = 1−9) of O2 were found to be 1.1 ± 0.1, 1.9 ± 0.1, 2.0 ± 0.2, 2.3 ± 0.3, 2.5 ± 0.3, 3.0 ± 0.3, 4.0 ± 0.5, 4.8 ± 0.5, and 8.0 ± 0.8 (×10-14 cm3 molecule-1 s-1). And the kv (v = 1−8) quenched by CO2 were 5.7 ± 0.1, 5.9 ± 0.1, 5.3 ± 0.2, 3.4 ± 0.3, 2.4 ± 0.3, 2.2 ± 0.2, 2.0 ± 0.2, and 1.8 ± 0.2 (×10-14 cm3 molecule-1 s-1), respectively. The trend of the (kv) with v for CO/O2 system was explained by a V−V energy transfer mechanism of single channel. For the CO/CO2 s...