Aa. Ionin et al., Theoretical modelling and experimental studies of the multi-quantum vibration exchange in vibrationally excited CO molecules, J PHYS D, 34(14), 2001, pp. 2230-2236
Studies of the vibration-vibration (VV) exchange in CO molecules excited up
to vibration quantum numbers, nu = 20 have been performed both theoretical
ly and experimentally. A new kinetic model which takes into account the mul
ti-quantum VV exchange in the temperature range T = 100-300 K is described
for the first time. A description is given of the experimental methodology
allowing for studies of the effects of the relaxation of the vibrational di
stribution after a sudden disturbance. The disturbance of the vibrational d
istribution is produced by a Q-switched short pulse of single line radiatio
n in fundamental band. The relaxation is studied by measuring the laser pul
se energy of the second pulse initiated by resonator Q-switching produced w
ith a variables time delay relative to the first pulse. A set of kinetic ra
te constants accepted in the model for various gas temperatures, vibration
level numbers and number of exchanged vibration quanta from 1 to 4 is prese
nted. The good agreement between the experimental data and the results of t
he advanced theory is the first direct evidence in support of the multi-qua
ntum exchange model.