Product translational energies

Fig. 15. (a) Product translational energy distributions, (b) product center-of-mass... 

Compared to the H-atom Rydberg tagging technique,65 the resolution of the present method is somewhat worse, by about a factor of two. This loss in resolution, however, is realized in general only for photodissociation studies. In a typical crossed beam experiment, the product translational energy resolution is usually limited by the energy spread of the initial collision energy rather than the detection scheme. On the other hand, the present... 

The time-of-flight spectrum of the H-atom product from the H20 photodissociation at 157 nm was measured using the HRTOF technique described above. The experimental TOF spectrum is then converted into the total product translational distribution of the photodissociation products. Figure 5 shows the total product translational energy spectrum of H20 photodissociation at 157.6 nm in the molecular beam condition (with rotational temperature 10 K or less). Five vibrational features have been observed in each of this spectrum, which can be easily assigned to the vibrationally excited OH (v = 0 to 4) products from the photodissociation of H20 at 157.6 nm. In the experiment under the molecular beam condition, rotational structures with larger N quantum numbers are partially resolved. By integrating the whole area of each vibrational manifold, the OH vibrational state distribution from the H2O sample at 10 K can be obtained. In... 

Fig. 14. The product translational energy distributions at very low translational energy region. The solid lines are the experimental results while the dotted lines are the simulated distributions, (a) The photolysis laser polarization is perpendicular to the detection axis, (b) the photolysis laser polarization is parallel to the detection axis.

Fig. 15. The product translational energy distributions for the OH + D channel from the HOD photodissociation at 121.6 nm with the photolysis laser polarization parallel as well as perpendicular to the detection direction.

The TOF spectra were then converted into the product translational energy distributions. Figure 26 shows the product translational energy distributions at the LAB angles of 117°, 30° and —50° for the 0(1D) reaction with H2 at both j = 0 and 1 rotational levels. These angles correspond... 

Fig. 29. The CM product translational energy distributions at the forward and backward scattering direction for the 0(1D) +D2 — OD + D reaction at two collision energies (a) 2.0 kcal/mol, and (b) 3.2 kcal/mol.

Fig. 31. The product translational energy distributions measured at different laboratory angles for the H + HD —> H2 + D reaction at the collision energy of 0.5 eV.

Fig. 6. (a) Center-of-mass 0(3Pj) +H(2S) product translational energy distribution,... 

Fig. 27. Product translational energy distribution of the H-atom production channel in the secondary photodissociation of ethoxy radical at 193.3 nm. The onsets of the relevant electronic states of the possible CH3CHO product are indicated in the figure. The signals from the primary photodissociation of ethanol are labelled. (FYom Xu et al.171)...

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