Vibrational State-Resolved\nDifferential Cross Sections\nof the F + CH<sub>4</sub> → HF + CH<sub>3</sub> Reaction at\nthe Collision Energies of 3.1–13.8 kcal/mol

We report a high-resolution crossed molecular beam experiment\ninvestigating\nthe reaction dynamics of the F + CH<sub>4</sub> → HF + CH<sub>3</sub> reaction across a broad range of collision energies (3.1–13.8\nkcal/mol). By using time-sliced velocity map imaging within the crossed\nmolecular beam apparatus, we obtain correlated angular distributions\nand branching ratios for various product pairs (CH<sub>3</sub>(ν),\nHF(ν′)). The resolved reactive rainbow-like features\nthat display a distinct bulge in the angular distribution in different\nchannels reveal the formation of vibrationally ground and excited\nstates of the methyl radical accompanied by different rovibrationally\nexcited HF products. These findings suggest distinct reaction dynamics\nfor channels leading to vibrationally excited methyl radicals compared\nto those forming ground-state methyl radicals.