Raw images of product CD3 at the collision energy of 4.6 kcal/mol: (a) v 2 = 1 and (b) v 2 = 2. The reactant beam directions in the center-of-mass frame are given in (a). On the images along the beam direction, there were minor background spots arising from non-resonant multiphoton ionization of the reactant molecules.
Separated flux-velocity contour maps of product CD3 from insertion and abstraction pathways at the collision energy of 4.6 kcal/mol: (a) v 2 = 1 and (b) v 2 = 2. Density-to-flux simulation 28 and symmetrization are required to transform the raw images into these maps. The intensity of each contour has been weighted by u 2 (u is the center-of-mass velocity of CD3) in accordance with conventional representation of differential cross section. The contour intensities for the same CD3 vibrational state are normalized to one another, but not for different CD3 states. The vibrational quantum number of the counterpart product OD is shown as v ′. The direction of the CD4 beam defines the forward scattering direction as 0 in (a).
The percentage (A/I) of product CD3(v 2 = 0,1,2) population from abstraction mechanism (A) over insertion mechanism (I) at different collision energies. The solid squares are our experimental data, and the solid lines are drawn through the data points to estimate the threshold of the abstraction pathway.
Raw images of the CD3 products detected via (a) , (b) , and (c) REMPI bands from the O(1 D) + CD4 → OD + CD3 reaction at the collision energy of 6.8 kcal/mol. The reactant beam direction in the center-of-mass frame is given in (a).
Separated flux-velocity contour maps of product CD3(v = 0) of different rotational energies from the insertion and abstraction pathways at the collision energy of 6.8 kcal/mol. The results indicate that some of the CD3 products are highly rotationally excited. While accumulating images, detecting laser energy was fixed at different positions of the Q( ) peak, in order to observe different rotationally excited CD3. The abstraction proportion is 16% and 11% for (a) N ≈ 5 and (b) N ≈ 10. At (c) N ≈ 15, no vibrationally resolved feature was observed, so the abstraction contribution can be regarded as zero.
Product vibrational state correlation of the O(1 D) + CD4 → OD + CD3 reaction at the collision energy of (a) 1.6, (b) 2.8, (c) 4.6, and (d) 6.8 kcal/mol. In the figure, v 2 is the umbrella mode vibrational quantum number of CD3, while v ′ is the vibrational quantum number of OD. The vertical coordinate is the proportion in the total product (including abstraction and insertion).
Averaged vibrational and translational energy (kcal/mol) of products from abstraction mechanism at different collision energies (E C).
Relative intensities of product CD3 at different vibrational states (all normalized to the v 2 = 0 intensities).
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