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Published on: July 27, 2022
Rotational Mode Specificity in Cl + CH4(v3=1,|jNl⟩): Role of Reactant's Vibrational Angular Momentum
Huilin Pan1, Yuan Cheng1, Kopin Liu1
1Institute of Atomic and Molecular Sciences (IAMS), Academia Sinica , P.O. Box 23-166, Taipei, Taiwan 10617.
Abstract:
The effect of initial rotational states in the reaction of antisymmetric-excited CH4(v3=1,|jNl⟩) with Cl atom was investigated in a crossed-beam, product-imaging experiment over the collisional energy (Ec) range of 2-5 kcal mol(-1). We found that while the initial rotational excitations exert a noticeable effect on total reactivity, they leave little imprint on the more detailed product-state and angular distributions. This finding echoes the previous conclusion in the analogous Cl + CHD3(v1=1,|NK⟩) reaction. However, the rotational enhancement factor is substantial at low Ec and then becomes insignificant at higher Ec, in contrast to the Cl + CHD3 case. A more intriguing finding is the role of the vibrational angular momentum (l) in promoting the reactivity. A heuristic picture is proposed to rationalize the observations.
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