Energetics of the reaction of CH3D with Cl to produce either CH3 + DCl (left hand barrier) or CH2D + HCl (right hand barrier). The barrier heights are consistent with calculations on other isotopologues and the observed relative yields of CH3 and CH2D for different collision energies. The translation energy distributions shown in the figure correspond to the production of Cl atoms by photolysis of Cl2 at three different wavelengths: 309 nm, 355 nm, and 416 nm. The label 2ν4 marks the energy of the overtone vibration with one quantum in each of two C–H bonds.
Relative yields of CH3 (red trace) and CH2D (blue trace) from the reaction of CH3D with translationally energized Cl atoms. The three sets of data are for collision energies of E coll = 1970 cm−1 (λ phot = 309 nm), E coll = 1280 cm−1 (λ phot = 355 nm), and E coll = 610 cm−1 (λ phot = 416 nm). The relative yield of CH3 decreases with decreasing translational energy, as shown by the ratio of the areas of the features. The wavelengths on the abscissa are values in vacuum.
Vibrational action spectra for the reaction of vibrationally excited CH3D with Cl to produce CH2D(ν1) at three different relative translational energies. The comb above the spectra and the dots above individual features mark rotational transitions of the A 1-symmetry stretching vibration. The unmarked features are transitions to the E-symmetry states, and all of the spectra are normalized to the isolated transition, rR3(3), at 6066 cm−1.
Product state REMPI signals for the CH2D products of the reaction of vibrationally excited CH3D with Cl to produce CH2D(ν1), having only C–H stretching excitation, and CH2D(ν1 + ν4), having both C–H stretching and bending excitation, at three different relative translational energies. The smooth black lines are fits of Lorentzian lineshapes to the features.
Photolysis wavelengths, cross sections, collisions energies, and distribution widths.
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