We present the results of an accurate quantum scattering study of collisional energy transfer in the collinear He+CS2 system, considering energies up to 75 kcal/mol. These results are generated using a coupled channel calculation, with vibrational eigenfunctions obtained from a discrete variable representation method. Detailed comparisons with the results of classical trajectory calculations are performed so as to assess classical/quantum correspondence for energy transfer moments, and for the energy transfer probability distribution function. We find very good agreement of the energy averaged first moments over a wide range of molecular vibrational energies provided that the translational energy is not too low (translational temperatures significantly below 300 K). The second moments, as well as 〈ΔE〉up and 〈ΔE〉down show less quantitative agreement, especially at low temperatures. The energy transfer distribution functions show considerable mode-specific behavior, but the overall envelope is approximately exponential in |ΔE| except for a spike near |ΔE|=0. Only weak dependence of the energy averaged results on the strength of intramolecular coupling is noted.
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry