Vibrational relaxation of D2 in 3He and 4He mixtures

The rates of vibrational relaxation of D2 in 3He and 4He mixtures have been studied by the laser-induced vibrational fluorescence technique. The relaxation rates of HCl/D2/3He and HCl/D2/4He mixtures at 296°K show cross sections of V → T, R energy transfer as σD2−4He = 9.5 ± 1.1 × 10−23 cm2, σD2−3He = 12.5 ± 1.5 × 10−23 cm2. These measured cross sections should provide an ideal test for existing scattering theory calculations.