Vibrational excitation of SF6 in collisions with He atoms

Vibrational excitation of SF₆ molecules in collisions with He atoms is studied using a vibrational close-coupling, rotational infinite-order-sudden method of calculation. Integral and differential cross sections for excitation of the triply degenerate ν₆ and ν₅ vibrational modes of SF₆ are reported for thermal collisional energies. Excitation of the ν₆ mode is found to be particularly efficieny. The cross sections are much larger than those calculated previously for the excitation of the bending mode in the He + CO₂ system. The differential cross sections are backward peaked.