Quasiclassical trajectories on a pairwisehyphen;additive potentialhyphen;energy surface have been used to compute statehyphen;tohyphen;state cross sections for energy transfer in Ar+HF. Interest is focused upon relaxation from high vibrationhyphen;rotation states. Purehyphen;rotational energy transfer in excited vibrational states, vibrational relaxation, and the effect of relative translational energy on the energy transfer were also investigated. Most of the calculations were carried out for 1.0 eV relative translational energy. Initial vibrational statesvi= 0, 2, 4, and 6 and initial rotational statesJi= 0, 10, 20, 30, and 40 were studied at this collision energy. The energy transfer for initial statevi= 4,Ji= 20 was studied at the initial relative translational energies 0.2, 0.4, 0.6, 0.8, and 1.0 eV. For collisions of Ar with highly excited HF the dominant energy transfer isVhyphen;R. The energy transfer results in an increase in the rotational state for downward vibrational transitions and a decrease in rotational state for upward vibrational transitions. The results suggest that purehyphen;rotational energy transfer for low levels of rotational energy (Jilsim;10), even in high vibrational states, should be accurately described by the rigidhyphen;rotor approximation. None of the energy transfer processes has a strong dependence on the initial relative translation energy, however, the influence is not negligible in all cases.
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