Jl. Cooper et Jc. Whitehead, ROTATIONAL AND VIBRATIONAL-ENERGY TRANSFER IN CH-(B-(2)SIGMA(-)), Journal of physical chemistry, 98(34), 1994, pp. 8274-8278
Rate constants have been obtained for rotational and vibrational energ
y transfer within the B ((2) Sigma(-)) state of CH by collisions with
Ar and N-2. By using laser photolysis of CHBr3 as the source of CH (B)
, it was possible to produce a wide range of rotational and vibrationa
l levels (N less than or equal to 15, v less than or equal to 1). The
rate constants for rotational relaxation are found to be comparable to
gas kinetic (k < 1.8 X 10(-10) cm(3) molecule(-1) s(-1)). At the peak
, the rates for vibrational energy transfer are of a similar order of
magnitude, particularly for argon. These results, coupled with the obs
erved propensity for multiquantum changing collisions for rotational r
elaxation, suggest that there is a small attractive interaction betwee
n the CH (B) radical and the relaxing gas.