(Color online) The optimized structures of the species of interest calculated by the G3//B3LYP method. For the calculated structures, unscaled harmonic frequencies, moments of inertia, and zero-point corrected energies (using scaled frequencies), see the supplementary documents (Ref. 6).
Minima and transition states on the potential energy surface for some of the dissociation and isomerization channels of the radical intermediates important in the reaction. Energies shown are those relative to INT C3; they are calculated at the G3//B3LYP level and are zero point corrected. INT B can also isomerize over a higher barrier then dissociate to (not shown). The “isom path” not shown from INT E to or, with a much smaller branching fraction, to , is kinetically disfavored as it involves INT E isomerizing, over a barrier at an energy of relative to INT C, to a lower energy radical intermediate that can then dissociate to these products. INT E instead dissociates easily over a much lower barrier and looser transition state to form . The likely route to is instead from the INT F radical intermediate formed from addition of the OH to the center carbon of allene; the dominant path from INT F to is shown in dashed line. A much higher barrier pathway from INT F to products, which begins with a H atom transfer analogous to the 1,3 shift in allyl radicals, is not shown. The overlaid curves show the internal energy distributions of the radicals produced from photodissociation of 2-chloro-2-propen-1-ol at (as determined from the measured velocity distributions of the momentum-matched cofragments and correcting for the fact that the radicals produced in coincidence with have less internal energy).
(Color) Raw images of (a) obtained with the probe laser at via the transition; (b) obtained with the probe laser at via the transition. Each image consists of and is constructed by accumulating signals from approximately 50 000 shots. The distance of on the phosphor screen corresponds to the width of in the images. The polarization direction of the probe laser is shown.
The center-of-mass translational energy distributions derived from the corresponding images in Fig. 3 and the total center-of-mass translational energy distributions for all Cl fragments (solid line) obtained from the weighted sum of the individual Cl distributions.
Gas-phase ultraviolet absorption spectrum of 2-chloro-2-propen-1-ol from .
Bond dissociation energies, average thermal vibrational energy of the chloropropenol reactant, and energy available post-dissociation (relative to the zero-point level of INT C3) in for four different conformers for the reactant chloropropenol molecule obtained from G3//B3LYP calculations. Conformer 3 is calculated to be the most stable one of 2-chloro-2-propen-1-ol, as shown in the fourth column.
A comparison of the CBS-QB3 energies calculated by Park et al. (Ref. 4) with the G3//B3LYP energies calculated in this study for some of the radical intermediates, transition states, and products shown in Fig. 2.
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