Crossed Molecular Beam Study of the F+D-2 (v=1, j=0) Reaction

The reaction dynamics of the fluorine atom with vibrationally excited D-2 (v=1, j=0) was investigated using the crossed beam method. The scheme of stimulated Raman pumping was employed for preparation of vibrationally excited D-2 molecules. Contribution from the reaction of spin-orbit excited F*(P-2(1/2)) with vibrationally excited D-2 was not found. Reaction of spin-orbit ground F(P-2(3/2)) with vibrationally excited D-2 was measured and DF products populated in v'=2, 3, 4, 5 were observed. Compared with the vibrationally ground reaction, DF products from the vibrationally excited reaction of F(P-2(3/2))+D-2 (v=1, j=0) are rotationally "hotter". Differential cross sections at four collision energies, ranging from 0.32 kcal/mol to 2.62 kcal/mol, were obtained. Backward scattering dominates for DF products in all vibrational levels at the lowest collision energy of 0.32 kcal/mol. As the collision energy increases, angular distribution of DF products gradually shifts from backward to sideway. The collision-energy dependence of differential cross section of DF(v' =5) at forward direction was also measured. Forward-scattered signal of DF(v'=5) appears at the collision energy of 1.0 kcal/mol, and becomes dominated at 2.62 kcal/mol