An analytical representation of the ground potential energy surface (2A′) of the H+Cl2→HCl+Cl and Cl+HCl→HCl+Cl reactions, based on <i>ab initio</i> calculations

González, Miguel; Hijazo, J.; Novoa, Juan J.; Sayós, R.

doi:10.1063/1.475713

Cited by 31 publications

(25 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This was confirmed in previous QCT studies carried out by our group on reaction ͑1͒. 19,32 The same type of analytical expression 33 ͑many-body expansion͒ used in previous studies of our group (O( 3 P)ϩH(CH 3 ), 6 NϩNO, 34 O( 3 P)ϩCS, 35 HϩCl 2 , 36 NϩO 2 , 37 and HϩClF 38 ͒ was also used 32 to describe the PES of reaction ͑1͒:…”

Section: Potential Energy Surfacesupporting

confidence: 72%

Theoretical study of the dynamics, stereodynamics, and microscopic mechanism of the O(1D)+CH4(X 1A1)→OH(X 2Π)+CH3(X 2A2″) reaction

González

Hernando

Puyuelo

et al. 2000

The Journal of Chemical Physics

Self Cite

View full text Add to dashboard Cite

A previously reported potential energy surface ͑PES͒ and a new barrierless PES ͑both based on ab initio data and describing the CH 3 group as a pseudoatom͒ were used to study the O( 1 D)ϩCH 4 →OHϩCH 3 reaction with the quasiclassical trajectory ͑QCT͒ method. The new PES accurately reproduces the experimental rate constant values, in contrast to the previous PES. The QCT study was mainly performed at the relative translational energy (E T ) resulting from the photodissociation of N 2 O at 193 nm (͗E T ͘ϭ0.403 eV͒, although the collision energy obtained from the photodissociation of O 3 at 248 nm (͗E T ͘ϭ0.212 eV͒ was also considered. Good agreement between theory and experiment was obtained for the OH vibrational populations and for the OH rotational populations for the vЈу2 vibrational levels, while the rotational distributions for vЈϭ0 -1 are more excited than in the experiment. The QCT results at E T ϭ0.403 eV satisfactorily reproduce the experimental kkЈ angular distribution of the state-specific channel OH(vЈϭ4, NЈϭ8) and the corresponding E T Ј distribution. For OH(vЈϭ0, NЈϭ5) the reproduction of these properties is poorer, especially for the E T Ј distribution. At 0.403 eV the contribution of the abstraction mechanism to the reaction mode is negligible and two insertion like mechanisms ͑with fast or slow elimination͒ are found to be predominant, as suggested experimentally. The discrepancies observed between the QCT and experimental results can be explained on the basis of the defective description of the insertion/slow elimination mechanism provided by the model.

show abstract

Section: Potential Energy Surfacesupporting

confidence: 72%

Theoretical study of the dynamics, stereodynamics, and microscopic mechanism of the O(1D)+CH4(X 1A1)→OH(X 2Π)+CH3(X 2A2″) reaction

González

Hernando

Puyuelo

et al. 2000

The Journal of Chemical Physics

Self Cite

View full text Add to dashboard Cite

show abstract

“…As a complementary example, we want to present the atom transfer reaction HCl + Cl → Cl + HCl (7) which is an example for a symmetric double-well potential and a prototypic heavy-light-heavy reaction. [117][118][119][120][121] Thermal rate constants for this reaction can not be observed experimentally except of the reaction with isotopically labelled chlorine. Therefore, we restrict ourselves to the presentation of the instantons and paths.…”

Section: Reaction Of Hcl + CLmentioning

confidence: 99%

Comparison of classical reaction paths and tunneling paths studied with the semiclassical instanton theory

Meisner

Markmeyer

Bohner

et al. 2017

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

Atom tunneling in the hydrogen atom transfer reaction of the 2,4,6-tri-tert-butylphenyl radical to 3,5-di-tert-butylneophyl, which has a short but strongly curved reaction path, was investigated using instanton theory. We found the tunneling path to deviate qualitatively from the classical intrinsic reaction coordinate, the steepest-descent path in mass-weighted Cartesian coordinates. To perform that comparison, we implemented a new variant of the predictor-corrector algorithm for the calculation of the intrinsic reaction coordinate. We used the reaction force analysis method as a means to decompose the reaction barrier into structural and electronic components. Due to the narrow energy barrier, atom tunneling is important in the abovementioned reaction, even above room temperature. Our calculated rate constants between 350 K and 100 K agree well with experimental values. We found a H/D kinetic isotope effect of almost 10 at 100 K. Tunneling dominates the protium transfer below 400 K and the deuterium transfer below 300 K. We compared the lengths of the tunneling path and the classical path for the hydrogen atom transfer in the reaction HCl + Cl and quantified the corner cutting in this reaction. At low temperature, the tunneling path is about 40% shorter than the classical path.

show abstract

“…placed in the center of mass of the radical has been considered. The same type of analytical expression ͑many-body expansion 39 ͒ and programs 40,41 used in previous works of our group ͓e.g., N( 4 S)ϩNO, 42 O( 3 P)ϩCS, 43 H( 2 S)ϩCl 2 and Cl( 2 P) ϩHCl, 44 and N( 4 S)ϩO 2 45 reactions͔ have also been employed here. According to our approach, the analytical PES can be represented as follows:…”

Section: B Analytical Potential Energy Surfacementioning

confidence: 99%

Ab initioground potential energy surface, VTST and QCT study of the O(3P)+CH4(X 1A1)→OH(X 2Π)+CH3(X 2A2″) reaction

González

Hernando

Millán

et al. 1999

The Journal of Chemical Physics

Self Cite

View full text Add to dashboard Cite

An ab initio study of the ground potential energy surface ͑PES͒ of the O( 3 P)ϩCH 4 →OHϩCH 3 reaction has been performed using the second-and fourth-order Møller-Plesset methods with a large basis set. A triatomic analytical ground PES with the methyl group treated as an atom of 15.0 a.m.u. has been derived. This PES has been employed to study the kinetics ͓variational transition state theory ͑VTST͒ and quasiclassical trajectory ͑QCT͒ rate constants͔ and dynamics ͑QCT method͒ of the reaction. The ab initio points have also been used directly to calculate the VTST rate constant considering all atoms of the system. The best VTST methods used lead to a good agreement with the experimental rate constant for 1000-2500 K, but QCT rate constant values are about one-third the experimental ones for 1500-2500 K. The cold QCT OH(vϭ0) rotational distribution arising from the simulation of the reaction with O( 3 P) atoms produced in the photodissociation of NO 2 at 248 nm is in good agreement with experiment, while the very small QCT OH(vϭ1) population obtained is consistent with measurements. The triatomic PES model derived in this work may be used in studies of the kinetics and dynamics under conditions where the methyl group motions are not strongly coupled to the motions leading to reaction.

show abstract

An analytical representation of the ground potential energy surface (2A′) of the H+Cl2→HCl+Cl and Cl+HCl→HCl+Cl reactions, based on ab initio calculations

Cited by 31 publications

References 27 publications

Theoretical study of the dynamics, stereodynamics, and microscopic mechanism of the O(1D)+CH4(X 1A1)→OH(X 2Π)+CH3(X 2A2″) reaction

Theoretical study of the dynamics, stereodynamics, and microscopic mechanism of the O(1D)+CH4(X 1A1)→OH(X 2Π)+CH3(X 2A2″) reaction

Comparison of classical reaction paths and tunneling paths studied with the semiclassical instanton theory

Ab initioground potential energy surface, VTST and QCT study of the O(3P)+CH4(X 1A1)→OH(X 2Π)+CH3(X 2A2″) reaction

Contact Info

Product

Resources

About