Analytical potential energy surface for O+C2H2 system

Garashchuk, Sophya; Rassolov, Vitaly A.; Braams, Bastiaan J.

doi:10.1016/j.cplett.2013.09.060

Cited by 4 publications

(3 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The preference for backward scattering with respect to the direction of the reagent O atoms increases with increasing collision energy (see Fig. S2a-d The present experimental results can be interpreted in more detail by considering the available information on the underlying potential energy surface as determined in electronic structure calculations by Nguyen et al 7 and Garashchuk et al 45 According to their calculations, the O( 3 P) + C 2 H 2 reaction is initiated by electrophilic O-addition onto a C-atom of acetylene, with the formation of the bound triplet addition trans-HCCHO intermediate. Because of the large internal energy content, the trans-HCCHO can either convert to its rotamer cis, undergo a C-H bond fission with the formation of H + HCCO(X 2 A 00 ) or rearrange to triplet ketene by a 1,2-H shift.…”

Section: Discussionsupporting

confidence: 51%

See 1 more Smart Citation

Dynamics of the O(3P) + C2H2 reaction from crossed molecular beam experiments with soft electron ionization detection

Leonori

Balucani

Capozza

et al. 2014

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

The reaction between ground state oxygen atoms, O((3)P), and the acetylene molecule, C2H2, has been investigated in crossed molecular beam experiments with mass-spectrometric detection and time-of-flight analysis at three different collision energies, Ec = 34.4, 41.1 and 54.6 kJ mol(-1). From product angular and velocity distribution measurements of the HCCO and CH2 products in the laboratory frame, product angular and translational energy distributions in the center-of-mass frame were determined. Measurements on the CH2 product were made possible by employing for product detection the recently implemented soft electron-ionization (EI) technique with low-energy, tunable electrons, which has permitted suppressing interference coming from the dissociative ionization of reactants, products and background gases. It has been found that the title reaction leads only to two competing channels: H + HCCO (ketenyl) and CO + CH2 (triplet methylene). The branching ratio of cross sections between the two competing channels has been determined to be σ(HCCO)/[σ(HCCO) + σ(CH2)] = 0.79 ± 0.05, independent of collision energy within the experimental uncertainty. This value is in line with that obtained in the most recent and accurate kinetics determination at room temperature as well as with that predicted from recent theoretical calculations based on statistical rate theory and weak-collision master equation analysis and on dynamics surface-hopping quasiclassical trajectory calculations on-the-fly on coupled triplet/singlet ab initio potential energy surfaces. The firm assessment of the branching ratio as a function of translational energy for this important reaction, besides its fundamental significance, is of considerable relevance for the implementation of theoretical models of hydrocarbon combustion.

show abstract

Section: Discussionsupporting

confidence: 51%

“…The dynamic results are discussed in light of the most recent electronic structure calculations of the relevant PESs. 7,41,45…”

Section: à9mentioning

confidence: 99%

Dynamics of the O(3P) + C2H2 reaction from crossed molecular beam experiments with soft electron ionization detection

Leonori

Balucani

Capozza

et al. 2014

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

show abstract

“…Molecular dynamics (MD) simulations, first introduced by Alder and Wainwright in 1959, have been utilized to study equilibrium and nonequilibrium phenomena for systems with various sizes, including but not limited to simple molecules in a uniform-phase environment or at the interface, − polymers, − biomolecules, − and solid-state materials. − Most MD methods are based on the Born–Oppenheimer (BO) approximation. , With the BO approximation, the nuclei of atoms in a molecule are moving in the average field of electrons, which is known as the potential energy surface (PES). As a result, MD implementations are typically composed of two building blocks: the approximation of the PES and the propagation of atomic positions.…”

Section: Introductionmentioning

confidence: 99%

Molecular Dynamics Simulations on Relaxed Reduced-Dimensional Potential Energy Surfaces

2019

View full text Add to dashboard Cite

Molecular dynamics (MD) simulations with full-dimensional potential energy surfaces (PESs) obtained from high-level ab initio calculations are frequently used to model reaction dynamics of small molecules (i.e., molecules with up to 10 atoms). Construction of full-dimensional PESs for larger molecules is, however, not feasible since the number of ab initio calculations required grows rapidly with the increase of dimension. Only a small number of coordinates are often essential for describing the reactivity of even very large systems, and reduced-dimensional PESs with these coordinates can be built for reaction dynamics studies. While analytical methods based on transition-state theory framework are well established for analyzing the reduced-dimensional PESs, MD simulation algorithms capable of generating trajectories on such surfaces are more rare. In this work, we present a new MD implementation that utilizes the relaxed reduced-dimensional PES for standard microcanonical (NVE) and canonical (NVT) MD simulations. The method is applied to the pyramidal inversion of a NH3 molecule. The results from the MD simulations on a reduced, three-dimensional PES are validated against the ab initio MD simulations, as well as MD simulations on full-dimensional PES and experimental data.

show abstract

Dissection of the multichannel reaction of acetylene with atomic oxygen: from the global potential energy surface to rate coefficients and branching dynamics

Zuo

Chen

et al. 2019

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

show abstract

Analytical potential energy surface for O+C2H2 system

Cited by 4 publications

References 14 publications

Dynamics of the O(3P) + C2H2 reaction from crossed molecular beam experiments with soft electron ionization detection

Dynamics of the O(3P) + C2H2 reaction from crossed molecular beam experiments with soft electron ionization detection

Molecular Dynamics Simulations on Relaxed Reduced-Dimensional Potential Energy Surfaces

Dissection of the multichannel reaction of acetylene with atomic oxygen: from the global potential energy surface to rate coefficients and branching dynamics

Contact Info

Product

Resources

About