Abstract
A potential energy surface that describes the title reaction has been constructed by interpolation of ab initio data. Classical trajectory studies on this surface show that the total reaction rate is close to that predicted by a Langevin model, although the mechanism is more complicated than simple ion-molecule capture. Only the product is observed classically. An estimate of the magnitude of rotational inelastic scattering is also reported.
This work was performed while S.R. was a guest at the Research School of Chemistry of the Australian National University, with financial support from the Ministry of Science, Research and Technology of Iran, and from Shiraz University. This work was performed using computational resources from the Australian National Computational Infrastructure National Facility.
I. INTRODUCTION
II. METHOD
A. Constructing the PES
B. Ab initio calculations
III. RESULTS
A. General features of the PES
B. reaction rate
C. Product branching
D. Inelastic scattering
IV. DISCUSSION AND CONCLUSION
Key Topics
- Interpolation
- 27.0
- Reaction rate constants
- 23.0
- Ion molecule reactions
- 21.0
- Chemical reaction cross sections
- 20.0
- Hydrogen reactions
- 19.0
Figures
Optimized structures of the stationary points at the level are shown. Bond lengths are indicated in angstroms and angles in degrees.
Optimized structures of the stationary points at the level are shown. Bond lengths are indicated in angstroms and angles in degrees.
The reaction scheme for is depicted. Relative energies of stationary points at the level are shown in , with the energy calculated using the triple zeta basis set given in parentheses.
The reaction scheme for is depicted. Relative energies of stationary points at the level are shown in , with the energy calculated using the triple zeta basis set given in parentheses.
The calculated total cross section at a translational energy of is shown as a function of the size of the ab initio data set (with data points in the order originally added to the set). Error bars show one standard error.
The calculated total cross section at a translational energy of is shown as a function of the size of the ab initio data set (with data points in the order originally added to the set). Error bars show one standard error.
The total reaction cross section is shown as a function of the relative kinetic energy. QCT results from the original PES (◼) and from the PES with the energies replaced by those calculated with the triple zeta basis set (●). Single standard error uncertainties are similar to the symbol size. The Langevin cross sections using the polarizabilities calculated at the and QCISD/aug-cc-pVTZ levels are shown as short and long dashes, respectively.
The total reaction cross section is shown as a function of the relative kinetic energy. QCT results from the original PES (◼) and from the PES with the energies replaced by those calculated with the triple zeta basis set (●). Single standard error uncertainties are similar to the symbol size. The Langevin cross sections using the polarizabilities calculated at the and QCISD/aug-cc-pVTZ levels are shown as short and long dashes, respectively.
Reaction probability is shown as a function of impact parameter for collisions at relative kinetic energies of (▲), (○), and (◼). The error bars show a single standard error uncertainty. The Langevin critical impact parameters at these energies are 7.35, 5.56, and 4.65 Å, respectively, each indicated by a vertical dotted line.
Reaction probability is shown as a function of impact parameter for collisions at relative kinetic energies of (▲), (○), and (◼). The error bars show a single standard error uncertainty. The Langevin critical impact parameters at these energies are 7.35, 5.56, and 4.65 Å, respectively, each indicated by a vertical dotted line.
The internal energy distribution of the product from QCT calculations with an initial relative translational energy of is shown, relative to the equilibrium energy.
The internal energy distribution of the product from QCT calculations with an initial relative translational energy of is shown, relative to the equilibrium energy.
The final average angular momentum of in nonreactive collisions is shown as a function of the impact parameter. The initial translational energy was and the fragment was initially irrotational. Results are shown for QCT calculations on PESs interpolating from 1300 to 2536 ab initio points.
The final average angular momentum of in nonreactive collisions is shown as a function of the impact parameter. The initial translational energy was and the fragment was initially irrotational. Results are shown for QCT calculations on PESs interpolating from 1300 to 2536 ab initio points.
Total rotationally inelastic cross sections are shown as functions of the size of the data set for different final values of . Cross sections are shown for final values of (solid line), (dashed line), and (dotted line). The initial relative translational energies were (upper plot) and (lower plot). Error bars indicate a single standard error uncertainty. results are considered unreliable.
Total rotationally inelastic cross sections are shown as functions of the size of the data set for different final values of . Cross sections are shown for final values of (solid line), (dashed line), and (dotted line). The initial relative translational energies were (upper plot) and (lower plot). Error bars indicate a single standard error uncertainty. results are considered unreliable.
Article metrics loading...
Full text loading...
Commenting has been disabled for this content