TY - JOUR
T1 - Quantum scattering studies of collisional energy transfer from highly excited polyatomic molecules
T2 - A bend-stretch model of He + CS2
AU - Lendvay, György
AU - Schatz, George C.
PY - 1997
Y1 - 1997
N2 - We present the results of an accurate quantum scattering study of collisional energy transfer in a bend-stretch model of the He + CS2 system, considering energies up to 45kcal/mol. These results are generated using a coupled channel method, 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 good agreement of the energy averaged first moments over a wide range of molecular vibrational energies. The second moments, as well as 〈ΔE〉up and 〈ΔE〉down show less quantitative agreement. The quantum energy transfer distribution functions show considerable mode-specific behavior, but the overall envelope is approximately exponential at large |ΔE\ with a broad spike near |ΔE| = 0. We analyze this behavior in terms of contributions from individual state-to-state transition probabilities. The corresponding classical distribution functions are very similar, showing better correspondence than was found for other models with smaller state densities.
AB - We present the results of an accurate quantum scattering study of collisional energy transfer in a bend-stretch model of the He + CS2 system, considering energies up to 45kcal/mol. These results are generated using a coupled channel method, 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 good agreement of the energy averaged first moments over a wide range of molecular vibrational energies. The second moments, as well as 〈ΔE〉up and 〈ΔE〉down show less quantitative agreement. The quantum energy transfer distribution functions show considerable mode-specific behavior, but the overall envelope is approximately exponential at large |ΔE\ with a broad spike near |ΔE| = 0. We analyze this behavior in terms of contributions from individual state-to-state transition probabilities. The corresponding classical distribution functions are very similar, showing better correspondence than was found for other models with smaller state densities.
KW - Chemical kinetics
KW - Computer experiments
KW - Energy transfer
KW - Quantum mechanics
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U2 - 10.1002/bbpc.19971010335
DO - 10.1002/bbpc.19971010335
M3 - Article
AN - SCOPUS:0011694449
SN - 0940-483X
VL - 101
SP - 587
EP - 594
JO - Berichte der Bunsengesellschaft/Physical Chemistry Chemical Physics
JF - Berichte der Bunsengesellschaft/Physical Chemistry Chemical Physics
IS - 3
ER -