Quantum State-Resolved Scattering of F + CH4 -> HF(v,J) + CH3; Nascent HF(v,J) Product State Distributions

Published

September 1, 2000

Author(s)

W W. Harper, S A. Nizkorodov, David Nesbitt

Abstract

State-to-state reactive scattering of F+CH₄->HF(Ņ,J)+CH₃ is studied usihng crossed supersonic jets and high-resolution (δŅnearly equal to}0.0001 cm^-1) IR laser direct absorption techniques. Rovibrational state-resolved HF column-integrated absorption profiles are obtained under single collision conditions and converted to populations via appropriate density-to-flux transformation. Nascent rovibrational distributions in each HF(Ņ,J) state are reported. Summed over all product rotational levels, the nascent vibrational quantum state populations for HFŅ [(Ņ=3 0.106(3): (Ņ=2) 0.667(14); (Ņ=1) 0.189(27); (Ņ=O) 0.038(78); 2ς error bars] are in agreement with previous flow cell studies by Setser, Heydtmann, and co-workers [Chem. Phys. 94, 109 (1985)]. At the rotational state level, however, the current studies indicate nascent distributions for HF(Ņ,J)that are significantly hotter than previously reported, ostensibly due to reduced collisional relaxation effects under supersonic jet conditions. Final HF rotational states from F+CH₄ are observed near the maximum energetically accessible J values in both the Ņ=2 and Ņ=3 vibrational manifolds, which provides experimental support for a bent F-H-C transition state structure.

Citation

Journal of Chemical Physics

Volume

113

Issue

No. 9

Pub Type

Journals

Keywords

reactive scattering

Citation

Harper, W. , Nizkorodov, S. and Nesbitt, D. (2000), Quantum State-Resolved Scattering of F + CH₄ -> HF(v,J) + CH₃; Nascent HF(v,J) Product State Distributions, Journal of Chemical Physics (Accessed July 18, 2024)